Abstract: Aerosol Index (AI) data was used to study the spatio-temporal distribution of ultraviolet (UV)-absorbing aerosols over East Asia. The main conclusions are as follows. In addition to continuity from the Earth Probe (EP)/Total Ozone Mapping Spectrometer (TOMS) AI to the Ozone Monitoring Instrument (OMI) AI, which differs from the Nimbus 7 (N7)/TOMS AI to EP/TOMS AI, good consistency was shown among N7/TOMS, EP/TOMS, and OMI AI. UV-absorbing aerosols are mostly located in the Taklimakan Desert, Kumutage Desert, Qaidam Basin Desert, Gurbantünggüt Desert, Midwestern Inner Mongolian Autonomous Region, Southern Mongolia, Northeastern China, and North China. Moreover, UV-absorbing aerosols have obvious characteristics of inter-monthly variation. Rotated Empirical Orthogonal Function (REOF) analysis can isolate source domains of UV-absorbing aerosols and provide quantitative information on the relative strengths of these sources.