OBJECTIVE Tinnitus is a common and disabling condition that largely remains undertreated in Sri Lanka. Currently, standardized tools that assess and monitor the treatment of tinnitus or the distress it causes are unavailable in either of the two main vernacular languages prevalent in Sri Lanka. The Tinnitus Handicap Inventory (THI) is used internationally to measure tinnitus-induced distress and to monitor treatment efficacy. In this study, we validated the Sinhala version of the THI (THI-Sin). Subjects and. METHODS The THI was translated into Sinhala and back translated into English and finalized by independent translators. The THI-Sin questionnaire and the 12-item General Health Questionnaire (GHQ-12) and Visual Analog Scale of tinnitus annoyance (VAS) were administered to 122 adults who visited the otolaryngology clinic of Colombo North Teaching Hospital, Ragama, Sri Lanka. RESULTS THI-Sin scores showed satisfactory internal consistency (Cronbach's α=0.902) and were significantly correlated with the GHQ-12 and VAS scores. Factor analysis of the THI-Sin confirmed a three-factorial structure, which did not correspond to the original THI subscales. CONCLUSIONS We observed significant reliability and validity of the THI-Sin tool for evaluation of tinnitus-induced handicaps among the Sinhalese-speaking population of Sri Lanka.