It depends - but please more details so others can Help
Technically speaking yes you can. But it really depends on case to case basis. If you have an expried H1B (after you applied for I485) you would be fine, but if you had some other visa and it expried before I-485 things can be tricky.
Keep in mind that using AP would trigger a secondary verification at the port of entry to US (about 90% chance) and if you status was not "legal" per INS standards, you might be denied an entry to US (even with a valid AP in your hand).
Hope this helps
