US citizen going US to Hong Kong 2 days, TaiPei, Shanghai 3days(+1hr? )then US need Chinese visa.

Gary, if you plan to fly from Taiwan to Shanghai, stay in Shanghai for 72 hours and then fly back to Taipei, then you are not qualified for 72 hours free transit. The 72 hours at Shanghai airport is counted from 00:00 of next day. Your interval is ok. However, the departure place can't be the same as your destination.

For this reason, I think you should apply for a L type for your mainland trip.

Thanks for your prompt and helpful reply. But, I think I have left some confusion in my description of my itinerary.

For the last leg, I plan to fly from Taipei(TPE) to Shanghai(PVG) then direct to the usa(ORD or LAX). I would arrive at PVG about 2PM on August 22nd and my plane is scheduled to depart at 4:10PM August 25th. I am hopeful that I don't need a visa for this part of the trip since the 72 hour starts at midnight the night of the 22nd and ends at midnight the night of the 25th.

It is true that, on my way to Asia, I am flying from the USA(WAS) to Hong Kong(HKG) and then to Taipei(TPE). I don't think I need a visa to do this part.

I am hopeful the first part of my trip doesn't affect the visa requirement for the second part of my trip. And that I have interpreted the 72 hour visa requirements correctly.

Best,
Gary

Gary, your understanding is correct. You are eligible for the 72-hour free transit policy in Shanghai. The route is OK.