Transtympanic infusion of 4% lidocaine was performed as a treatment for cochlear tinnitus, and its efficacy was investigated. The overall efficacy rate for the 292 patients with 369 affected ears was 81%. In the investigation of the treatment results in cases of different underlying ear diseases, the efficacy rate was high for tinnitus accompanying sudden deafness and labyrinthine vertigo. However, vestibular symptoms, such as vertigo and nausea, developed after lidocaine infusion. No permanent side effects were noted. Lidocaine infusion is thought to be a useful treatment option for tinnitus and should be considered before surgical treatment.