Eight different soils of the State of São Paulo were studied as to their phosphorus fixation capacity. The effect of concentration of the phosphate solution, time of contact of the solution with the soil and alternatively drying and wetting the sample was also evaluated. Fixation tests were performed with undisturbed soil samples as well as with samples of which organic matter and iron oxides had been removed. Phosphorus fixation was higher in latosols and "terra roxa estruturada" than in podzolic soils but decreased in all soils upon removal of iron oxides. Removal Of organic matter and the drying-and-wetting process increased fixation in some cases and decreased it in others.