Objective To investigate the pathological features in the rat membranous nephropathy model induced by rabbit anti-rat FxlA.Mehtods 64 Sprague-Dawley (S-D) male rats were used for trial.18 of them were randomly assigned as the normal group and another 18 as the normal rabbit serum group.28 rats were assigned as the model group.The rats in normal group were given a single peritoneal injection of 8 mL/kg body wt of physiological saline.The rats in normal rabbit serum group were given a single peritoneal injection of 8 mL/kg body wt of normal rabbit serum.The rats of model group were given a single peritoneal injection of 8mL/kg body wt of rabbit anti-rat FxlA antibody.One week after the injection,24 hour urine protein excretion quantity (24 h UPQ) were detected for the rats in model group.The results were abandoned if their 24 h UPQ were less than 5 mg.At the end of the 2nd and 4th week,9 rats were randomly chosen from each groups and their 24 h UPQ,biochemical index and pathology changes of renal were detected.Results 24 h UPQ,CHOL and TG were significantly higher in model group than those in other groups at the the end of the 2nd and 4th week (P ＜ 0.05).ALB were significantly lower in model group than those in other groups at the end of the 2nd and 4th week(P ＜0.05).The renal histopathology of the rats in model group under the light microscope,immunofluorescence microscope,and electron microscope showed the typical features of membranous nephropathy.Conclusions The pathological features of the rat model induced by once intraperitoneal injection of rabbit antirat Fx1A serum were similar to human membranous nephropathy.