Polyacrylamide is widely used as soil conditioner to improve soil capacity for water retention and anti-erosion,while its impact on soil nutrients' retention and release is not clear.In this paper,Lou soil was amended with PAM at varied ratios of 0.1%,0.2% and 0.4%,and technique of phosphorus isotherm absorption and desorption was employed to study the effect of PAM on phosphorus retention and release in Lou soil.The results showed that PAM amended with soil can prohibit the physical absorption of phosphorus and led to decrease of absorption amount and maximum adsorption amount(X_m),but the effect PAM on phosphorus chemical absorption is small.Soil amended with PAM increase the release of absorbed phosphorus,especially for the physical absorbed phosphorus.