OBJECTIVE：To establish a method for the determination of related substances in bifonazole raw material. METHODS： HPLC method was performed on the column of Kromasil C18 with mobile phase of methanol-0.02 mol/L phosphoric acid （adjusted pH to 7.5 with triethylamine）（70 ∶ 30，V/V） at a flow rate of 1.0 ml/min， detection wavelength was 258 nm， volume injection was 20 μl，and the column temperature was 40 ℃. RESULTS：The linear range was 0.05-0.25 μg/ml for bifonazole（r＝0.999 6），0.05-0.25 μg/ml for impurity A （bifonol）（r＝0.999 7） and 0.05-0.25 μg/ml for impurity B （4-C isomer）（r＝0.999 5）； the detection limits were 8.2 ng/ml， 7.5 ng/ml and 8.4 ng/ml， and the quantification limits were 27.1 ng/ml， 24.7 ng/ml and 27.8 ng/ml， respectively； RSDs of precision and reproducibility tests were lower than 1％； recovery of impurity B was 95.13％-101.29％（RSD＝1.89％，n＝9）； both impurity A and impurity B were were detected in the 3 batches of samples. CONCLUSIONS： The method is accurate， sensitive and reproducible， and can be used for the determination of the related substances in bifonazole raw material.