To grasp the film cooling characteristics of the turbine blade tip in transonic flow, the pressure sensitive paint technique was used to experimentally obtain the effects of the tip clearance gap and mass flow ratio on the film cooling performance of the blade tip. The results indicate that, under conditions of low mass flow ratio, increasing the tip clearance height effectively enhances the film coverage in the mid-chord region of the blade tip. However, when the mass flow ratio is high, changes in the tip clearance height have an insignificant effect on the distribution of film cooling efficiency in this region. Under conditions of small tip clearance heights, the cooling coverage in the mid-chord region deteriorates gradually as the mass flow ratio increases. In contrast, with larger tip clearance heights, an improvement in cooling coverage is only observed when the mass flow ratio increases from 0.1%+0.05% to 0.14%+0.07%.