Abstract: A generate assembly and a lighting element for a pneumatic tool includes a body having a channel and a first passage defined therein. The first passage has a first end communicating with an exhauster of the pneumatic tool and a second end extending to communicate with the channel and defining an opening in an inner periphery of the channel. A second passage defined in the body for exhausting exhaust gas. A generator is mounted in the body for generating electric power to the lighting element. The generator has a turbine extending into the channel and eccentrically corresponding to the opening in the inner periphery of the channel such that exhaust gas, from the pneumatic tool, drive the turbine due to the eccentric relation between the turbine and the opening. A sleeve is securely mounted around the body for airtightly closing the channel in the body.