Background First-contact care,accessibility,continuity of care,comprehensiveness of care,coordination,and patient-centered care are core domains and key features of primary care. Measuring these core domains from patients' perspectives is is an important domain and component of primary care quality evaluation. However,domestically developed instruments for assessing core domains of primary care have not yet existed in China. Objective This study aimed to develop a Chinese version of Assessment Survey of Primary Care(ASPC) with domestic and international characteristics. Methods We developed a Chinese version of ASPC and tested its validity based on a four-stage approach. In the first stage,research on related theoris and studies,and expert consultation were conducted to construct the conceptual framework and connotative elements of the scale.In the second stage,the original item pool was formed through literature review and in-depth interviews with stakeholders. A pilot study was conducted with 373 patients to refine items and develop the test version of the scale. In the third stage,a multi-level sampling strategy was used to select 1 185 patients from diversified primary care institutions to pre-test the test version of the scale. In the fourth stage,the reliability and validity of the instrument were tested according to the consensus-based standards for the selection of health status measurement instruments(COSMIN) checklist,and then the final version of the scale was developed. Results Results of the exploratory factor analysis showed that the Chinese version of ASPC consisted of nine subdimensions of six dimensions,including first-contact care,accessibility,continuity of the physician-patient relationship(covering subdimensions of longitudinal and stable relationships between physicians and patients,mutual trust between physicians and patients,and physicians' responsibility),comprehensiveness(covering subdimensions of health,lifestyle and psychological counseling and guidance,health examination,disease screening,interventions and suggestions),coordination(covering subdimensions of coordination conditions and services),and patient-centered care. The Cronbach's α coefficient of the scale was 0.915,while the coefficients of the nine subdimensions were all greater than 0.65(ranged from 0.659 to 0.863),indicating high reliability. In the confirmatory factor analysis,the chi-square/df value and the comparative fit index value of the scale were 2.828 and 0.875,respectively. For all subdimensions,all the composite reliability values were larger than 0.7,and the average variance extracted values were larger than 0.5 or close to 0.5,responding that the convergent validity was appropriate for all sub-dimensions. The scale score or the score in each dimension was positively associated with patients' satisfaction. Moreover,there were significant differences in the scale score between two groups of patients with or without a contracted family doctor. Conclusion The Chinese version of ASPC has good psychometric properties with good scale and subscale internal consistency reliability and content validity,as well as structural and construct validity consistent with the theoretical conception. The theoretical framework of the scale is consistent with the six internationally recognized core domains of primary care,ensuring that the empirical research results of this instrument are comparable to similar foreign research results. The subdimensions of the instrument conform to the conditions of the Chinese healthcare system and can describe the performance of Chinese primary care comprehensively and accurately.