BackgroundThis study aimed to explore the factors that affect insured’s perceptions of convenience of the basic medical insurance (PCBMI) in Harbin, China and to diagnose the key problems to further propose corresponding measures. The findings provide evidence-based support for the reform of convenience of the basic medical insurance system (BMIS) and the cultivation of public literacy.MethodsWe adopted a mixed methods design composing a multivariate regression model using the data from a cross-sectional questionnaire survey (n= 1045) of residents who were enrolled for BMIS in Harbin to identify the factors influencing the PCBMI. A quota sampling method was further adopted. Semi-structured interviews were then conducted with 30 important information providers selected by convenience sampling. Interpretative phenomenological analysis was employed to summarize and analyze the key problems.ResultsOverall, approximately 51% of respondents reported poor PCBMI. The logistic regression model showed that insured without outpatient experience within two weeks (OR = 2.522, 95% CI = 1.267–5.024), had poorer levels of understanding of basic medical insurance information (OR = 2.336, 95% CI = 1.612–3.386), lived in rural areas (OR = 1.819, 95% CI = 1.036–3.195), had low levels of annual out-of-pocket medical expenses (OR = 1.488, 95% CI = 1.129–1.961), and were more likely to give the PCBMI a worse evaluation than their counterparts. The results of the qualitative analysis showed that the key problem areas of the PCBMI were the design of the BMIS, the cognitive biases of the insured, publicity information about the BMIS, and the health system environment.ConclusionsThis study found that in addition to the design of BMIS, the cognition of the insured, the BMIS information publicity and the health system environment are also the key problems hindering PCBMI. While optimizing system design and implementation, Chinese policymakers need to focus on the insured with low PCBMI characteristics. Moreover, it is necessary to focus on exploring effective BMIS information publicity methods, supporting public policy literacy and improving the health system environment.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12889-023-15993-1.