Exhibit 5.1

                      [LETTERHEAD OF LOWENSTEIN SANDLER PC]

May 24, 2007


NeoStem, Inc.
420 Lexington Avenue
Suite 450
New York, NY 10170

Gentlemen:

You have  requested our opinion in  connection  with the  registration  with the
Securities and Exchange  Commission under the Securities Act of 1933, as amended
(the "Act"),  of 25,000,000  shares of Common  Stock,  par value $.001 per share
("Common Stock"), of NeoStem,  Inc. (the "Company") on Post-Effective  Amendment
No. 2 to a Registration Statement on Form S-8 (the "Post-Effective  Amendment").
The shares of Common  Stock to which the  Post-Effective  Amendment  relates are
issuable pursuant to the Company's 2003 Equity Participation Plan (the "Plan").

We have examined and relied upon originals or copies, authenticated or certified
to  our   satisfaction,   of  all  such   corporate   records  of  the  Company,
communications or certifications of public officials,  certificates of officers,
directors and  representatives  of the Company,  and such other  documents as we
have  deemed  relevant  and  necessary  as the basis of the  opinions  expressed
herein.  In making such  examination,  we have  assumed the  genuineness  of all
signatures,  the authenticity of all documents tendered to us as originals,  and
the  conformity  to  original  documents  of all  documents  submitted  to us as
certified or photostatic copies.

Based upon the  foregoing and relying upon  statements of fact  contained in the
documents  which we have  examined,  we are of the  opinion  that the  shares of
Common  Stock  offered by the  Company  pursuant  to the Plan,  when  registered
pursuant to the Act and paid for in full by the  participants in accordance with
the Plan, will be, when issued, legally issued, fully paid and non-assessable.

We  hereby  consent  to  the  filing  of  this  opinion  as an  exhibit  to  the
Registration Statement and any amendment thereto.

Very truly yours,

/s/
LOWENSTEIN SANDLER PC