The invention relates to a pile chuck. The pile chuck comprises a clamping device for clamping the pile head of a prefabricated pile, the clamping device is mounted on a rack of a pile driver in a lifting mode, a downward opened clamping port for holding the pile head is formed in the clamping device, the clamping port is arranged into a structure with the adjustable size, and connected with an adjusting assembly, and the adjusting assembly adjusts the size of the clamping port. According to the pile chuck, by arranging the adjustable clamping port and a positioning assembly, the purpose of quickly clamping and fixing the prefabricated pile and driving the prefabricated pile into the ground through the pile chuck can be achieved, the clamping efficiency of pile chuck is further improved, the requirements of fast piling are met, and operation is convenient and fast.