A torque-adjustable pneumatic tool comprises a body, a trigger assembly, and a torque-adjusting module. The body has an outlet tunnel. The trigger assembly is mounted to the body. The torque-adjusting module is mounted to the body, communicates with the outlet tunnel, and has a silencer, an adjusting bolt, and a piston lid. The silencer has a recess and an exhaust portion communicating with the recess. The exhaust portion has a threaded hole and at least one exhaust hole that are separately disposed through the exhaust portion. The adjusting bolt is movably mounted to the threaded hole of the silencer from a side away from the body, and engages with the silencer through threads. The piston lid is fixed to the adjusting bolt and is able to enter the recess.