Abstract: Given the harsh testing conditions, high cost, and low accuracy of production profile testing of offshore horizontal wells, an production profile testing method based on intelligent solid tracers was proposed for offshore horizontal wells. The release pattern and influential factor of intelligent solid tracers were investigated. It is shown that the release rate of solid tracers is high upon the initial contact with fluids; it slows down and eventually reaches equilibrium, as the contact time lapses. Moreover, solid tracers have high tolerances to high temperatures and salinity. The release rate is directly proportional to temperature and inversely proportional to salinity. The release rate is independent of the flushing rate. Based on the release pattern of solid tracers and the single-phase steady flow model of horizontal wells, the horizontal well production profile interpretation method was developed and practiced in the field, together with the active switch water control technique and AICD water control technique. The field application demonstrates that before adjusting the water control tool, the liquid production contributions of the heel, middle, and toe sections of the tested well are 88.57%, 5.43%, and 6%, respectively; they change to 50%, 17.19%, and 32.81%, correspondingly, after the water control tool is adjusted. This validates the performance of the water control tool to balance the liquid production of each section. This technology is of great practical significance for promoting high-efficiency cost-effective recovery of offshore horizontal wells in China.