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                                    FORM 6-K
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                            Report of Foreign Issuer

                      Pursuant to Rule 13a-16 or 15d-16 of
                       the Securities Exchange Act of 1934

                         For the month of October, 2005

                        Commission File Number: 333-07654


                                  ENDESA, S.A.
                 (Translation of Registrant's Name into English)

                              Ribera del Loira, 60
                               28042 Madrid, Spain
                     (Address of principal executive office)

        Indicate by check mark whether the registrant files or will file
              annual reports under cover of Form 20-F or Form 40-F:
                      Form 20-F      X        Form 40-F
                                   -----                   -----

       Indicate by check mark if the registrant is submitting the Form 6-K
             in paper as permitted by Regulation S-T Rule 101(b)(1):
                         Yes                     No          X
                                   -----                   -----

       Indicate by check mark if the registrant is submitting the Form 6-K
             in paper as permitted by Regulation S-T Rule 101(b)(7):
                         Yes                     No          X
                                   -----                   -----

          Indicate by check mark whether by furnishing the information
        contained in this Form, the Registrant is also thereby furnishing
     the information to the Commission pursuant to Rule 12g3-2(b) under the
                        Securities Exchange Act of 1934:
                         Yes                     No          X
                                   -----                   -----

  If "Yes" is marked, indicate below the file number assigned to the registrant
                     in connection with Rule 12g3-2(b): N/A
                                                        ---


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                                  RELEVANT FACT


New York,  October 21,  2005.-  Given the  confusion  created by Gas Natural SDG
S.A.'s  recent   statement   regarding   the  supposed   existence  of  required
authorizations  to  effect  the legal  separation  of its gas  distribution  and
transportation activities,  Endesa S.A. deems it necessary to make the following
observations for the general knowledge of the market:

     1.   At the time it  announced  the  tender  offer for the  acquisition  of
          Endesa  S.A.'s  shares,  Gas Natural SDG S.A. had not  undertaken  the
          separation  of its gas  distribution  and  transportation  activities,
          because it lacked  -according to Endesa's legal advisors- the required
          administrative  approvals,  as a result of which the  National  Energy
          Commission  cannot  grant Gas Natural SDG S.A. any approval to acquire
          share capital.

     2.   According to the information  notified by Gas Natural SDG to the CNMV,
          by Relevant Fact number  61.180,  dated October 3, 2005  (available at
          www.cnmv.es),  its Board of Directors  approved the  separation of its
          distribution  assets  project  through a transfer to Gas Natural  SDG,
          S.A.,  "transfer  [that] will be immediately  completed  through (...)
          share  capital  increases  in  Gas  Natural  Distribucion  SDG".  Said
          announcement  expressly indicated that "from a legal,  operational and
          accounting  perspective,  the  separation  of  activities  will become
          effective  as of October 1,  2005".  Nonetheless,  Gas Natural did not
          point  out  that  such  transaction   required  prior   administrative
          approval.

     3.   Gas Natural has repeated  these  statements  in a Relevant  Fact filed
          with the  CNMV on  October  19,  2005  (number  61.519,  available  at
          www.cnmv.es).  In that  announcement  the gas company stated that "the
          separation  of activities  became  effective as of October 1, 2005, in
          accordance   with  the  respective   Public  Deed  [of  share  capital
          increase], which, in addition, has been registered with the commercial
          Registry on October 17, 2005".





     4.   On October 4, Endesa  requested  that the National  Energy  Commission
          (CNE)  require Gas Natural to request to the  Commission  the required
          prior  authorizations  for the creation of two companies  (Gas Natural
          SDG  Transporte  and  Gas  Natural  SDG   Distribucion)  and  for  the
          subsequent  transfer of gas  transportation  and distribution  assets.
          Likewise,   Endesa   requested   that  the   Commission   suspend  the
          authorization process for Gas Natural's tender offer for Endesa.

     5.   On October 11, Gas Natural SDG requested the CNE's  authorization  for
          the creation of the affiliates and for the transfer of  transportation
          and distribution  assets,  if it deemed  necessary.  On October 13 and
          October  18,  the  CNE  decided,  with  the  dissenting  vote  of  two
          commissioners,   that  such   authorizations   should   be   processed
          simultaneously with Gas Natural's tender offer for Endesa, without the
          latter being suspended.

     6.   Gas Natural SDG persists  today with the CNMV, by Relevant Fact number
          61.584  (available at  www.cnmv.es)  in pretending to be in compliance
          with respect to the separation of activities  that it has  undertaken,
          indicating  that the transaction has been reported to the CNE and that
          transfer  of   distribution   facilities  is  not  subject  to  Madrid
          Autonomous Community's approval,  since "there are no rules regulating
          this issue".

     7.   Nonetheless,   Gas  Natural  SDG  has  omitted  to  mention  that  the
          separation of activities requires "CNE's prior approval" and not an ex
          post  notification,  pursuant  to  article  63.7  of the  LSH  and the
          additional  provision  11,3.1,14 of such Law.  Therefore,  Gas Natural
          SDG's  actions  have been taken is in an  irregular  manner and Endesa
          reserves such rights as it may have under applicable law.

     8.   In addition,  Gas Natural SDG disregards the fact that the transfer of
          natural gas distribution facilities also requires prior administrative
          approval  by the  applicable  regulatory  entity,  as  established  in
          articles 86 and 87 of the RD  1434/2002,  of December 27. This rule is
          applicable  both  to   Federal-regulated   natural  gas   distribution
          facilities  and to those subject to the  Autonomous  Communities  that
          have not set  their  own  regulation  on this  issue.  Therefore,  the
          autonomous  authorities  regulate  all  distribution  facilities  that
          affect a Community,  while the rest of the  facilities  are subject to
          Federal regulation.





     9.   Also untrue is Gas Natural  SDG's  statement in today's  Relevant Fact
          that  articles  86  and  87  of  the  RD  1434/2002  are  not  legally
          enforceable,  and even  less  that they  contradict  the  Hydrocarbons
          Sector Law (LSH). To start with,  every Royal Decree is presumed to be
          legal and  enforceable  and also bears the State  Council's  approval,
          which has not raised any  objection to the  authorization  requirement
          for the transfer of  distribution  facilities.  Secondly,  these rules
          complete,  in a perfectly  consistent way, article 73.2 LSH which only
          refers to the  notification of assets  transfer to the  administrative
          authority  that has issued  the  original  authorization.  It would be
          absurd to assume,  and would invite all sorts of fraud, that a company
          which requires an  authorization  to install and operate a natural gas
          distribution  facility (article 73.2, paragraph 1 LSH), could transfer
          it to a third party by way of a simple  notification,  without  giving
          the competent authority the chance to assess the managerial,  economic
          and technical  capabilities of the new owner. If the original owner of
          a  facility  has to be  authorized  by the  Administration,  so do its
          subsequent owners.

     10.  The  transfer  to  Gas  Natural   Distribucion  of  the   distribution
          facilities, without having the corresponding administrative approvals,
          suggests  that Gas Natural SDG S.A. may have incurred  "very  serious"
          administrative  violations, set in article 109.1.a) LSH, in performing
          regulated distribution activities (through the holding of ownership of
          distribution facilities) without having the required approval. As very
          serious  violations,   it  may  carry  a  fine  "from  100,000,001  to
          500,000,000 pesetas" and may give rise to termination or suspension of
          the  administrative   authorization  and  the  "subsequent   temporary
          prohibition  to operate  the  business  for a maximum  term of a year"
          (article  113.1.a and 113.4 of RD 1434/2002).  It should be noted that
          the  administrative  authorizations  are  required  to be  obtained in
          advance,  and therefore Gas Natural's actions have been taken is in an
          irregular  manner and Endesa reserves such rights as it may have under
          applicable law.





                                   SIGNATURES

Pursuant  to the  requirements  of the  Securities  Exchange  Act of  1934,  the
registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned, thereunto duly authorized.

                                                       ENDESA, S.A.

Dated: October 21st , 2005                       By:/s/ Alvaro Perez de Lema
                                                    ------------------------
                                                 Name:  Alvaro Perez de Lema
                                                 Title: Manager of North America
                                                        Investor Relations