EXHIBIT 5
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                                  June 14, 1999



Xybernaut Corporation
12701 Fair Lakes Circle
Fairfax, Virginia  22033

Gentlemen:

         We have acted as counsel to Xybernaut Corporation, a Delaware
corporation (the "Company"), in connection with a Registration Statement on Form
S-3 (the "Registration Statement") being filed with the Securities and Exchange
Commission under the Securities Act of 1933, as amended, relating to the
offering of 1,341,074 shares (the "Shares") of Common Stock, par value $.01 per
share (the "Common Stock"), which includes 182,482 shares issuable upon
conversion of 500 shares of the Company's Series D Preferred Stock and 1,083,591
shares issuable upon conversion of the Company's Series E Preferred Stock
(collectively, the "Conversion Shares"), par value $.01 per share and 75,000
shares issuable upon exercise of outstanding warrants (the "Warrant Shares").
The Warrant Shares and the Conversion Shares are collectively referred to herein
as the "Shares."

          In connection with the foregoing, we have examined originals or
copies, satisfactory to us, of the Company's (i) Certificate of Incorporation,
(ii) By-laws and (iii) resolutions of the Company's board of directors. We have
also reviewed such other matters of law and examined and relied upon all such
corporate records, agreements, certificates and other documents as we have
deemed relevant and necessary as a basis for the opinion hereinafter expressed.
In such examination, we have assumed the genuineness of all signatures, the
authenticity of all documents submitted to us as originals and the conformity
with the original documents of all documents submitted to us as copies or
facsimiles. As to any facts material to such opinion, we have, to the extent
that relevant facts were not independently established by us, relied on
certificates of public officials and certificates of officers or other
representatives of the Company.

         Based upon and subject to the foregoing, we are of the opinion that the
Shares, when issued upon conversion of the Series D and E Preferred Stock and
the Warrants, as applicable, will be validly issued, fully paid and
non-assessable.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement.


                                            Very truly yours,

                                         /s/ Parker Chapin Flattau & Klimpl, LLP
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                                             PARKER CHAPIN FLATTAU & KLIMPL, LLP


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