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                                                                     Exhibit 5.1

                                  June 26, 2001

Ascent  Pediatrics,  Inc.
187  Ballardvale  Street
Suite  B125
Wilmingotn,  Massachusetts  01887

     Re:   1999  Stock  Incentive  Plan  and  California  Stock  Option  Plan
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Ladies  and  Gentlemen:

     We have assisted in the preparation of a Registration Statement on Form S-8
(the  "Registration  Statement")  to  be  filed with the Securities and Exchange
Commission  relating  to  750,000 Depositary Shares, $.00004 par value per share
(the  "Depositary  Shares"),  of Ascent Pediatrics, Inc., a Delaware corporation
(the  "Company"),  issuable  under  the  1999  Stock  Incentive Plan and 200,000
Depositary Shares (collectively, the "Shares") of the Company issuable under the
California  Stock  Option  Plan  (collectively,  the  "Plans").

We have examined the Certificate of Incorporation of the Company and the By-laws
of  the  Company, each as amended and restated to date, and originals, or copies
certified  to  our satisfaction, of all pertinent records of the meetings of the
directors  and  stockholders of the Company, the Registration Statement and such
other  documents  relating  to  the  Company  as we have deemed material for the
purposes  of  this  opinion.

In  our  examination of the foregoing documents, we have assumed the genuineness
of  all  signatures  and  the  authenticity  of all documents submitted to us as
originals, the conformity to original documents of all documents submitted to us
as  certified,  photostatic  or  facsimile  copies,  and the authenticity of the
originals  of  any  such  documents.

We assume that the appropriate action will be taken, prior to the offer and sale
of  the  Shares  in accordance with the respective Plan, to register and qualify
the Shares for sale under all applicable state securities or "blue sky" laws. We
express no opinion herein as to the laws of any state or jurisdiction other than
the  state  laws  of  the  Commonwealth  of  Massachusetts, the Delaware General
Corporation  Law  statute  and the federal laws of the United States of America.
It  is  understood  that  this opinion is to be used only in connection with the
offer  and  sale  of  the  Shares while the Registration Statement is in effect.

Please  note  that  we  are  opining  only as to the matters expressly set forth
herein,  and  no  opinion  should  be  inferred  as  to  any  other  matters.

Based  on  the  foregoing,  we  are  of  the  opinion  that the Company has duly
authorized  for  issuance the Shares covered by the Registration Statement to be
issued  under  the  Plans,  as described in the Registration Statement, and such
Shares, when issued in accordance with the terms of the respective Plan, will be
legally  issued,  fully  paid  and  non-assessable.

We  hereby  consent  to  the  filing  of  this opinion with the Commission as an
exhibit  to  the  Registration  Statement in accordance with the requirements of
Item  601(b)(5)  of  Regulation  S-K  under  the Securities Act.  In giving such
consent,  we  do  not  hereby admit that we are in the category of persons whose
consent  is  required  under  Section  7  of the Securities Act or the rules and
regulations  of  the  Commission.

                                        Very  truly  yours,

                                        /s/  HALE  AND  DORR  LLP

                                        HALE  AND  DORR  LLP