Hey elitelee
It doesn't matter what envelope you use

As long as it fits your Letter of Request (LOR) and SAE/SASE (Self Addressed/Stamped Envelope) or photo if you want the celebrity to sign one of your own

... What do you mean by "envelope used in china"?

and Chinese envelope? If you send a self addressed envelope to them then the photo/autograph is likely to be sent back in that SAE {thumb2}
E.g.
Letter of Request, Self addressed envelope and IRCs
OR Self stamped addressed envelope, photo/item if you have any..
:
: GOES INTO
:
Envelope with the celebrity's address on it

.. If you use a SASE you don't need IRCs
If you have any further questions, perhaps these topics will help you
How to write to your favorite actor
What is an IRC
Or you can visit the stickies on the
Collecting Helpsection
Hope that helps
Nich
x