Objective To establish an RP-HPLC method for the determination of the content of safflor yellow A in Zhanjing Tinctura. Methods The chromatographic procedure was carried out in Symmetry C18 column(4.6mm?150 mm,5.0?m)with methanol-water-glacial acetic acid(7:93∶2)as the mobile phase,pH=2.80. The flow rate was 1.0 mL?min-1,column temperature was 20℃,and the detection wavelength was 402 nm. Results Safflor yellow A was well separated from other components. The standard curves of safflor yellow A showed linearity in the range of 0.096～0.960?g (r=0.9999). The average recovery was 98.80% with RSD being 2.95%(n=9). Conclusion This method is sensitive,simple and accurate,and can be used for the determination of safflor yellow A in Zhanjing Tinctura.