March 18, 2005


John Hancock World Fund
 on behalf of John Hancock Health Sciences Fund
101 Huntington Avenue
Boston, MA 02199

Ladies and Gentlemen:

In connection with the filing of a registration statement under the Securities
Act of 1933, as amended (the "Act"), on Form N-14, with respect to the shares of
beneficial interest of John Hancock Health Sciences Fund (the "Fund"), a series
of John Hancock World Fund (the "Trust"), a Massachusetts business trust, it is
the opinion of the undersigned that these shares when issued, will be legally
issued, fully paid and non-assessable.

In connection with this opinion it should be noted that the Trust is an entity
of the type generally known as a "Massachusetts business trust." Under
Massachusetts law, shareholders of a Massachusetts business trust may be held
personally liable for the obligations of the trust. However, the Trust's
Declaration of Trust disclaims shareholder liability for obligations of the
Trust and indemnifies any shareholder of the Fund, with this indemnification to
be paid solely out of the assets of the Fund. Therefore, the shareholder's risk
is limited to circumstances in which the assets of the Fund are insufficient to
meet the obligations asserted against the Fund's assets.

The undersigned hereby consents to the filing of a copy of this opinion as an
exhibit to the Trust's registration statement on Form N-14 and with the
Securities and Exchange Commission.

Sincerely,


/s/Brian E. Langenfeld
Brian E. Langenfeld
Attorney and Assistant Secretary