A simple and rapid capillary electrophoretic method was developed for the simultaneous determination of honokiol and magnolol inMagnolia officinalisextracts and dextrorphan was used as the internal standard. The running buffer was composed of 22.5 mM Na2HPO4and 10 mM Na2B4O7(pH 9.1–9.2). The linear calibration range was 2 – 20 μg/mL for honokiol and 5–50 μg/mL for magnolol. It was found that 0.95 ±0.02 mg of honokiol and 4.37 ± 0.08 mg of magnolol were contained in the ethanol (50%) extracts of 1 g ofMagnolia officinalis. The contents of these two active principles inMagnolia officinaliswas successfully determined within 12 min.