Background: The National Essential Medicine System (NEMS) is a new policy launched by the Chinese government in 2009. The effects of its introduction have been widely investigated. However, little research has focused on individual patients' perspectives. The purpose of this study was to examine current understanding and opinions of China's NEMS of primary care providers (PCPs) and patients. Methods: Providers (n = 134) and patients (n = 175) were examined based on self-completed questionnaire surveys conducted in 16 primary healthcare centers in Ningxia, northwestern China. Questions addressed the topics of: participants' socio-demographic characteristics; awareness of NEMS policies; perceptions of NEMS-related changes; satisfactions with NEMS. Results: The patients had a low awareness of NEMS while a majority of providers were familiar with NEMS. All participants were satisfied with the price and quality of essential medicines, but not satisfied with the quantity. Patients felt there had been a decrease in their total medical expenses per visit and improved pharmaceutical services. Most providers perceived no change in their personal or departmental income. The overall satisfaction rate related to NEMS among providers and patients was 92.54 and 93.31 %, respectively. Overall there was a link between knowledge about NEMS and satisfaction with the program: patients who had greater knowledge of reimbursement policy, and the providers with greater knowledge of NEMS, reported higher satisfaction. Conclusions: The findings revealed a high level of satisfaction towards NEMS among primary care providers and patients, which is a reflection of the improvements in the health care system. However, some patients' low awareness of NEMS should be paid attention to, as it could reduce their knowledge of essential medicines and hinder the full potential of NEMS.