Hat Yai is a city in southern Thailand near the Malaysian border. Located at 7°1′N 100°28′E, it has a population of 157,359 (2008) in the city itself and about 800,000 in the greater Hat Yai area. Hat Yai is the largest city of Songkhla Province, the largest metropolitan area in Southern, and third largest metropolitan area of the country. It is often mistaken as being the capital of the province, but Songkhla is the capital and the center of administration and culture, while Hat Yai is the business center. The two cities are considered as twin cities due to their close connection, and accordingly, Hat Yai and Songkhla form the Greater Hatyai-Songkhla Metropolitan Area.
The name "Hat Yai" is a short version of "Mahat Yai", meaning big mahat tree, a relative of jackfruits in genus Artocarpus