Abstract: 【Abstract】 Objective To determine the pharmacokinetics characteristics of mestinon-phospholipid complex（PBPLC） in rats. Methods This study adopted a single-dose, randomized, open-label, two-period crossover trial design. Twelve healthy rats were randomly divided into two groups. One group was orally administered with mestinon-phospholipid complex, and the other group was orally administered with reference mestinon solution (1.5 mg/kg of mestinon). The plasma concentrations of the drugs in ophthalmic vein bloods were determined using HPLC. The pharmacokinetic parameters were calculated with the aid of DAS2.1.1 software. Results Pharmacokinetic parameters of mestinon-phospholipid complex were Tmax 2 h, Cmax 22.79 μg·min/mL and AUC0-∞ 7128.21 μg·min/mL, which were different from those of free mestinon——Tmax 2 h, Cmax 6.00 μg/mL and AUC0-∞ 1772.36 μg·min/mL. The relative bioavailability of mestinon-phospholipid complex was 410.98 % of free mestinon. Conclusion The oral bioavailability of mestinon increases remarkably when administered as mestinon-phospholipid complex.