SKADDEN, ARPS, SLATE, MEAGHER & FLOM LLP
                               919 THIRD AVENUE
                           NEW YORK, NY 10022-3897

                              TEL:  (212) 735-3000
                              FAX:  (212) 735-2000

                                        October 9, 1997

          HSB Group, Inc.
          HSB Capital I
          c/o  HSB Group, Inc.
               One State Street
               Hartford, Connecticut 06102

          Ladies and Gentlemen:

                    We have acted as special counsel to HSB Group,
          Inc., a Connecticut corporation (the "Company"), and HSB
          Capital I, a business trust formed under the Business
          Trust Act of the State of Delaware (Chapter 38, Title 12,
          of the Delaware Code, 12 Del. C. SECTIONS 3801 et. seq.) (the
          "Issuer Trust"), in connection with the preparation of
          the Registration Statement on Form S-4 (the "Registration
          Statement") to be filed by the Company and the Issuer
          Trust with the Securities and Exchange Commission (the
          "Commission") on the date hereof.  The Registration
          Statement relates to the registration under the
          Securities Act of 1933, as amended (the "Act"), of
          $110,000,000 aggregate liquidation amount of Global
          Floating Rate Capital Securities, Series B (the "Capital
          Securities") in connection with a proposed exchange offer
          (the "Exchange Offer").

                    The Capital Securities are to be issued
          pursuant to the Amended and Restated Trust Agreement of
          the Issuer Trust, dated as of July 15, 1997 (the "Trust
          Agreement"), among Saul L. Basch, R. Kevin Price and
          Robert C. Walker, as administrative trustees, The First
          National Bank of Chicago, as property trustee (the
          "Property Trustee"), First Chicago Delaware Inc., as
          Delaware trustee, and the Company, as sponsor.

                    This opinion is being furnished in accordance
          with the requirements of Item 601(b)(5) of Regulation S-K
          under the Act.

                    In connection with this opinion, we have
          examined originals or copies, certified or otherwise
          identified to our satisfaction, of (i) the Registration
          Statement; (ii) an executed copy of the Registration
          Rights Agreement, dated as of July 15, 1997 (the
          "Registration Rights Agreement"), among the Company, the
          Issuer Trust, and Goldman, Sachs & Co.; (iii) the form of
          the Capital Securities and a specimen certificate
          thereof; (iv) the Certificate of Trust of the Issuer
          Trust filed with the Secretary of State of the State of
          Delaware on July 10, 1997; and (v) the Trust Agreement. 
          We have also examined originals or copies, certified or
          otherwise identified to our satisfaction, of such other
          documents, certificates and records as we have deemed
          necessary or appropriate as a basis for the opinions set
          forth herein.

                    In our examination, we have assumed the legal
          capacity of all natural persons, the genuineness of all
          signatures, the authenticity of all documents submitted
          to us as originals, the conformity to original documents
          of all documents submitted to us as certified or
          photostatic copies and the authenticity of the originals
          of such latter documents.  In making our examination of
          documents executed by parties other than the Issuer
          Trust, we have assumed that such parties had the power,
          corporate or other, to enter into and perform all
          obligations thereunder and have also assumed the due
          authorization by all requisite action, corporate or
          other, and execution and delivery by such parties of such
          documents and the validity and binding effect thereof on
          such parties.  As to any facts material to the opinions
          expressed herein which we did not independently establish
          or verify, we have relied upon oral or written statements
          and representations of officers, trustees and other
          representatives of the Company, the Issuer Trust and
          others.

                    Members of our firm are admitted to the bar in 
          the States of New York and Delaware, and we do not
          express any opinion as to the laws of any other
          jurisdiction other than the laws of the United States of
          America to the extent referred to specifically herein.

                    Based upon and subject to the foregoing, we are
          of the opinion that:

                    1. The Capital Securities have been duly
          authorized for issuance by the Issuer Trust, and when (i)
          the Registration Statement becomes effective and the
          Trust Agreement has been qualified under the Trust
          Indenture Act of 1939, as amended, and (ii) the Capital
          Securities are duly executed, authenticated and issued in
          accordance with the Trust Agreement and delivered and
          issued in the Exchange Offer as contemplated by the
          Registration Rights Agreement and the Registration
          Statement, the Capital Securities will be duly and
          validly issued, fully paid and nonassessable undivided
          beneficial interests in the assets of the Issuer Trust.
          We bring to your attention, however, that the holders of
          the Capital Securities may be obligated, pursuant to the
          Trust Agreement, to (i) provide indemnity and/or security
          in connection with, and pay taxes or governmental charges
          arising from, transfers of Capital Securities and the
          issuance of replacement Capital Securities and (ii)
          provide security and indemnity in connection with
          requests of or directions to the Property Trustee in
          connection with the exercise of its rights and powers
          under the Trust Agreement.

                    2. The holders of the Capital Securities will
          be entitled to the same limitation of personal liability
          extended to stockholders of private corporations for
          profit organized under the General Corporation Law of the
          State of Delaware. 

                    We hereby consent to the filing of this opinion
          with the Commission as an exhibit to the Registration
          Statement.  We also consent to the reference to our firm
          under the caption "Validity of Securities" in the
          Registration Statement.  In giving this consent, we do
          not thereby admit that we are included in the category of
          persons whose consent is required under Section 7 of the
          Act or the rules and regulations of the Commission.  This
          opinion is expressed as of the date hereof, and we
          disclaim any undertaking to advise you of any subsequent
          changes in the facts stated or assumed herein or of any
          subsequent changes in applicable law.

                                   Very truly yours,

                              /S/Skadden, Arps, Slate, Meagher & Flom LLP