OBJECTIVE: To improve the quality standard of Ejiao sanbao cream. METHODS: UPLC-MS was adopted to identify the donkey-hide glue in the preparation, the chromatographic conditions: column was Acquity UPLC BEH-C18 with mobile phase of acetonitrile-0.1% formic acid (gradient elution), volumetric flow rate was 0.3 mL/min,injection volume was 5 μL, ion source is electrospray ionization source, capillary voltage was 3.5 kV, capillary outlet voltage was 120 V, cone voltage was 50 V, desolvation temperature was 400 ℃, drying gas flow was 10 L/min, nebulizer pressure was 40 psi, collision energy was 10-45 V, scan range was m/z 200-1 500; detection mode was positive ion mode (ESI+),multiple reaction monitoring. HPLC was used to determine the contents of 4 hydrohyzing amino acid: column was Agela Venusil XBP-C18 with mobile phase A of acetonitrile-0.1 mol/L sodium acetate solution (36% acetic acid adjusted to pH 6.5) (7 ∶ 93,V/V) and B of 80% acetonitrile solution (gradient elution) at a flow rate of 1.0 mL/min, the detection wavelength was 254 nm, and column temperature was 43 ℃. RESULTS: The UPLC-MS peak of Equus asinus was clear and specific, without negative interference. The linear range was 0.081 9-0.655 2 μg for L-hydroxyproline (r=0.999 9), 0.186 2-1.489 6 μg for glycine(r=0.999 8), 0.070 3-0.562 0 μg for alanine (r=0.999 9) and 0.124 2-0.993 6 μg for L-proline(r=0.999 9); RSDs of precision, stability and reproducibility tests were lower than 2.0%; recoveries were 99.85%-103.69% (RSD=1.35%,n=6), 99.91%-103.93%(RSD=1.46%,n=6), 96.86%-101.27%(RSD=1.69%,n=6) and 97.44%-101.45%(RSD=1.54%,n=6), respectively. CONCLUSIONS: The improved standard can more effectively control the quality of Ejiao sanbao cream.