A gas torch includes a torch head assembly including a coupled base and a connected portion coupled to an outer periphery of the coupled base. A joint assembly, which is coupled to the coupled base and adapted for connecting to a nozzle of a bottled gas tank, includes a first joint member and a second joint member communicating with the first joint member. Two fasteners are inserted through the first and second joint members and engaged with the coupled base of the torch head. The joint assembly enables the torch head assembly to connect to different kinds of gas tanks.