Through in-lab thermostat incubation, investigation was done of changes in content of soil available phosphorus and soil phosphorus desorption kinetics, in vegetable garden soils different in parent material (basalt, granite, and river alluvium) in Guangdong Province, 30 d and 60 d after application of organic fertilizers (composted chicken droppings or commodity organic fertilizer). Results show that after the application of composted chicken manure or commodity organic fertilizer, contents of soil available phosphorus in all the three soils increased, with amplitudes showing composted chicken manure was higher in the effect than commodity organic fertilizer. Phosphorus desorption kinetic curves in all the treatments presented a period of rapid desorption followed by a period of slow desorption before reaching equilibrium. Phosphorus desorption in the soil was not only closely related to its initial available phosphorus content, but also to its parent material and the type of the organic fertilizer it received. Five kinetics equations were used to fit the kinetics curves of phosphorus desorption in the three soils different in parent material. The simplified Elovich equation, the Parabolic diffusion low equation and the Power function equation were better in fitting.