Background: Evaluating peritoneal fluid kinetics is of great value to the adjustment of peritoneal dialysis prescription. Therefore, in the present study, we developed a simple method, based on a membrane transport model, to evaluate the fluid transport characteristics of the peritoneal membrane in continuous ambulatory peritoneal dialysis (CAPD) patients. Methods: Patients’ peritoneal ultrafiltration (UF) volume was collected for 2 consecutive months. Membrane transport model and nonlinear least-squares regression analyses were applied to the pooled UF volume for the first month for fluid kinetic simulation and the data from the second month were used to evaluate the reliability and precision of simulated UF values. Results: Seventeen chronic peritoneal dialysis (PD) patients were selected for the present study. Simulated UF values based on the pooled UF volume in the first month correlated significantly with the actual measured UF values in the second month. By Bland-Atman plot, the width between the 95% limits of agreement fell within –133.3 to 154.2 ml with a mean difference of 10.5 ml. Conclusion: Our study showed that applying the fluid transport model and nonlinear least-squares regression analysis to the pooled actual UF value might be a good and simple way to predict peritoneal UF.