Exhibit 5.1




                                                              January 11, 2002


Data Systems & Software Inc.
200 Route 17
Mahwah, NJ 07430

                  Re:      Registration Statement on Form S-3

Ladies and Gentlemen:

     We have  acted as counsel  for Data  Systems &  Software  Inc.,  a Delaware
corporation  (the "Company"),  in connection with the Registration  Statement on
Form S-3 (Registration No.  333-90017) (the  "Registration  Statement") filed by
the Company under the  Securities  Act of 1933 for the purpose of registering an
aggregate of 141,509  shares of its common stock,  par value $.01 per share (the
"Shares"),  including (i) 21,509 shares (the  "Conversion  Shares")  issued upon
conversion of certain 0% Convertible  Subordinated Debentures convertible,  (ii)
an aggregate of 120,000 shares (the "Warrant  Shares") issuable upon exercise of
certain warrants issued pursuant to warrant  agreements  between the Company and
the holders of such warrants.

     On the basis of such  investigation as we have deemed necessary,  we are of
the opinion that (i) the Shares have been duly authorized for issuance, (ii) the
Conversion  Shares are fully paid and  non-assessable  shares of common stock of
the Company,  and (iii) the Warrant Shares, when issued upon due exercise of the
warrants in  accordance  with the terms of the  applicable  warrants and warrant
agreements,  will be fully paid and non-assessable shares of common stock of the
Company.

     We hereby  consent  to the  filing of this  opinion  as an  Exhibit  to the
Registration  Statement. In giving this consent, we do not thereby admit that we
come within the category of persons whose consent is required under Section 7 of
the  Securities  Act of 1933 or the Rules and  Regulations of the Securities and
Exchange Commission thereunder.

     Sheldon  Krause,  a member of our firm,  is the Secretary and a director of
the Company.

                                          Very truly yours,

                                          /s/ Ehrenreich Eilenberg & Krause  LLP