Sorption and desorption characteristics of four organic phosphates (OPs) with different molecular sizes and structures (glycerophosphate, GP; glucose-6-phosphate, G6P; adenosine triphosphate, ATP; myo-inositol hexakisphosphate, IHP) and inorganic phosphate (Pi) on three aluminium (Al) (oxyhydr)oxides (amorphous Al(OH)3, boehmite and α-Al2O3) were investigated. The maximum sorption amounts of OPs and Pi increased with decreasing crystallinity of the minerals on a per mass basis: α-Al2O3 < boehmite < amorphous Al(OH)3. With an exception of IHP sorption on amorphous Al(OH)3, the maximum surface area-based sorption densities increased with decreasing molecular weight (MW) of OPs and Pi: IHP < ATP < G6P < GP < Pi. Despite having the largest MW, IHP had greater sorption amounts on amorphous Al(OH)3 than the other OPs because of the transformation of surface complexes to surface precipitates. Sorption kinetics of OPs was first a rapid sorption followed by a long and slow sorption process. Of the three Al (oxyhydr)oxides, amorphous Al(OH)3 had the greatest first rapid sorption density and initial sorption rate of OPs within 5 minutes, both factors decreasing with increasing MW of OPs. The initial desorption percentages of OPs by KCl generally increased with decreasing MW of OPs, whereas the maximum desorption percentages of OPs by citrate were four to five times those achieved with KCl. Overall, strong specific sorption of OPs occurs on the surface of Al (oxyhydr)oxides, and molecular structure and size of OPs, as well as crystallinity and crystal structure of the minerals, are the key factors affecting the interfacial reactions and environmental behaviour of OPs.