The present study was performed on 32 patients in order to investigate the effect of low-power laser on their tinnitus. The patients were divided into two groups. One group received laser therapy and the other was given a placebo procedure. The effect was evaluated by the use of visual analogue scales. Within the patient group transiently evoked otoacoustic emissions (TEOAE) were measured before, during and after therapy. No significant difference between laser and placebo was found in annoyance or loudness of the tinnitus and in changes of TEOAE amplitude. These results indicate that there is no relationship between the effect of low-power laser and changes in cochlear micromechanics.