Hi, Ms. jen, it is both Ok for you to apply for a China visa in Philippines or in U.S. So you need make a decision.
Required Documents:
1.Passport: Your valid passport must have at least six (6) months of remaining validity and at least one blank visa page in it.
2.Application form: One completed Visa Application Form.
3.Photo: one photo of 2x2 square inch (black & white or color is acceptable) glued or stapled on the application form.
If you apply for it in U.S.A, you also need provide the original and photocopy of your US Green Card,Work Permit, valid US Visa or other additional documents asked by visa officials.
If you apply for it in Philippines, you'd better provide round-trip air ticket, hotel reservation in Beijing besides the above requirments.