Abstract: This paper investigates the determination method of propranolol in human plasma by HPLC. YWG-C₁₈H₃₇ column was used with CH₃OH-H₂O-0.2mol/L KH₂PO₄ 0.2mol/L Na₂HPO₄(460:40:0.7:4.7)as mobile phaseThe preparation of plasma sample: Transfer 0.5 ml plasma into a 5 ml polystyrene test tube with cap, add 0.8 ml of 0.2% sodium hydroxide solution into the plasma. Propranolol was extracted with ether. External standard was used for quantitation.The assay was evaluated using the reproducibility within day and day-to day, and demonstrated high precision. Their average coefficients of variation were 5.8% and 6.8% respectively. The standard curve was linear (r=0.9999)over the range of 0.05～2.00μg/ml, the average recovery was 95.9±4.5%.