Visa information for a Chinese to Thailand

To whom it may concern:
I am a U.S. national and my wife is Chinese national with U.S. permanent green card. We are currently live in China and wanted to travel to ThaiLand for Christmas holidays. With U.S. Passort I understood that I do not need a visa to travel. How about my wife? Does she needs one? If she required? Would it okay to get it in Thailand airport when she arrived? Thank you very much.