Background: A new policy which required deregulation on prices of off-patent medicines for women's health during procurement was introduced in China in September 2015. The current study examines this policy's impact on the affordability of essential medicines for women's health.Methods: Based on product-level panel data, a fixed effect regression model is employed by using procurement records from Hubei Centralist Tender for Drug Purchase platform. In the model, Affordability was measured with prices. The Competition consists of two parts: generic competition and therapeutic class competition which are measured with generic competitors and therapeutic substitutes. Instrument variable is used to deal with endogeneity.Results: The policy helped control prices of essential medicines for women's health. Generic competition helped control prices, however, therapeutic class competition caused higher prices.Conclusions: The new policy helped enhance the affordability of essential medicines for women's health as expected, which provides empirical evidence on price deregulation. Besides, generic competition is important in price control despite strict regulatory system in China.