A linkage mechanism includes a fixing member, a rotary member, a support member and a sliding module. A first end of the rotary member is rotatably assembled to the fixing member. A first end of the support member is rotatably hinged to the second end of the rotary member, and the second end of the support member is hinged with the sliding module. The sliding module includes a sliding member and a sliding rod slidably assembled to the sliding member. The sliding member is slidably mounted to the fixing member, and further hinged to the second end of the support member. The sliding member defines a sliding hole. The sliding rod is rotatably assembled to the rotary member together with the fixing member, and further slidably passing through the sliding hole of the sliding member. An electronic device using the linkage mechanism is also provided.