Exhibit 5
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               [JENKENS & GILCHRIST PARKER CHAPIN LLP LETTERHEAD]






                                 October 2, 2001

TII Industries, Inc.
1385 Akron Street
Copiague, New York 11726

              Re:     TII INDUSTRIES, INC.
                      --------------------

Dear Sir or Madam:

              We have  acted as  counsel  to TII  Industries,  Inc.,  a Delaware
corporation (the "Company"), in connection with a Registration Statement on Form
S-8 (the "Registration  Statement") being filed with the Securities and Exchange
Commission under the Securities Act of 1933, as amended (the "Act"), covering an
aggregate of 1,000,000  shares of the Company's common stock, par value $.01 per
share (the "Common Stock"), upon the exercise of options which have been, or may
from time to time be,  granted by the  Company  under the  Company's  1998 Stock
Option Plan (the "Plan") to employees and directors of, and  consultants to, the
Company  or any  parent  or  subsidiary  of the  Company,  and  such  additional
indeterminate  number  of shares  of  Common  Stock as may be  issued  under the
anti-dilution provisions of the Plan.

              In rendering the opinions  expressed  below,  we have examined the
Restated Certificate of Incorporation of the Company, as amended, the By-laws of
the Company, as amended, and minutes of the corporate proceedings of the Company
relating to the Plan.  In addition,  we have examined and relied upon such other
matters of law,  certificates  and  examinations of public  officials as we have
deemed  relevant to the  rendering of this  opinion.  We have not examined  each
option contract in respect of options granted under the Plan. We have,  however,
examined  the form of option  contract  which the  Company has advised us is the
form of option contract used by it under the Plan. We have also been informed by
the Company  that each option  contract  between the Company and option  holders
under  the Plan is  substantially  in the form of the  option  contract  we have
examined.  In all of our  examinations,  we have  assumed  the  accuracy  of all
information  furnished  to us and  the  genuineness  of all  documents  and  the
conformity  to  originals  of  all  documents  submitted  to  us  as  certified,
conformed,  facsimile or photostatic copies thereof,  as well as the genuineness
of all signatures on all such documents.

              Our  opinion is  limited  to the date  hereof and we do not in any
event undertake to advise you of any facts or circumstances  occurring or coming
to our attention subsequent to the date hereof.

              Finally,  we are counsel admitted to practice only in the State of
New  York,  and  we  express  no  opinions  as to  the  applicable  laws  of any
jurisdiction  other than those of the State of New York,  the General  Corporate
Law of the State of Delaware and the United States of America.



              Based upon and  subject to the  foregoing,  we are of the  opinion
that the  shares of the  Company's  Common  Stock to be issued  pursuant  to the
exercise of options granted or to be granted under the Plan will be, when issued
pursuant  to  the  provisions  of the  Plan,  legally  issued,  fully  paid  and
non-assessable.

              We hereby  consent to the  filing of a copy of this  opinion as an
exhibit to the  Company's  Registration  Statement  with respect to the Plan. In
giving this consent,  we do not thereby admit that we are within the category of
persons  whose  consent is required  under  Section 7 of the Act,  the rules and
regulations of the Securities and Exchange Commission  promulgated thereunder or
Item 509 of Regulation S-K promulgated under the Act.

                                        Very truly yours,


                                    /s/ JENKENS & GILCHRIST PARKER CHAPIN LLP
                                        JENKENS & GILCHRIST PARKER CHAPIN LLP