The photocatalytic (PC) degradation kinetics of sulfosalicylic acid (SSA) at different pH using TiO2 microspheres were elucidated by modeling. The resultant model had special consideration of adsorption and pH. The adsorption isotherms showed that the LC/MS2-identified intermediateswereweakly adsorbed on the TiO2 microspheres, thus their adsorptionwas neglected in the modeling. By contrast, the SSAwas significantly adsorbed, thus its adsorption retained as an item in the model. Consequently, a non-first-order modelwas obtained. Through the modeling, itwas elucidated that the reaction rate increased non-linearly with the SSA adsorption equilibrium constant. Meanwhile, it was elucidated that a pH increase favored the hydroxyl radical production to accelerate the SSA degradation, while impeded the SSA adsorption to slower it, hence a neutral pH caused the fastest SSA degradation.