Abstract: The stability of yinhuang injection was effectively solved by adding the stabilizer polyvinyl alcohol. The stability of yinhuang injection was investigated through the influencing factor test and accelerated test. The results showed that under the conditions of influence factor test with high temperature (60℃), low temperature (4℃) and strong light exposure (4500±500 lx), and accelerated test of 6 months (with temperature of 40±2℃ and humidity of 75%±5%), the change of baicalin content in yinhuang injection prepared according to pharmacopeia standards (control group) was not significant, and the traits and identification also met the requirements, while the pH value and chlorogenic acid content were not stable with significant changes. However, the pH value, chlorogenic acid and baicalin content of yinhuang-polyvinyl alcohol injection (treatment group) were stable with no significant changes, and the traits and identification were also in line with the requirements. This indicated that the yinhuang-polyvinyl alcohol injection by adding 2% PVA in the formula and adjusting the pH value of the injection to 5.5-7.0 was more stable and effective than the yinhuang injection prepared according to pharmacopoeia standard.