Objective To understand the spatial distribution and influencing factors of secondhand smoke (SHS) exposure in healthcare facilities in China, and to provide a reference for the development of regional tobacco control strategies and measures in these facilities.

Methods Data were collected from the 2022 China Adult Tobacco Survey, including relevant data from non-collectively residing Chinese residents aged ≥ 15 years old and above in 31 provinces (autonomous regions, municipalities) across the country. Geoda 1.22 statistical software was used to conduct spatial autocorrelation analysis and ordinary least squares (OLS) spatial regression model analysis to explore the main influencing factors of SHS exposure in healthcare facilities and their spatial heterogeneity.

Results In 2022, the SHS exposure rate in Chinese healthcare facilities was 13.6%. The regions with the lowest exposure rates were Shanghai city and Beijing city (exposure rates between 0% and 5%), and the region with the highest exposure rate was Jiangxi province (exposure rate between 25% and 30%). Global spatial autocorrelation analysis showed that the spatial distribution of SHS exposure rates in Chinese healthcare facilities in 2022 was positively correlated and spatially clustered (Moran′s I = 0.359, Z = 3.430, P = 0.002), indicating that regions with higher exposure rates were surrounded by regions with similarly high exposure rates. Local spatial autocorrelation analysis showed that Qinghai province, Sichuan province, Chongqing city, Guizhou province, Hunan province, and Hubei province were all in high-high cluster areas, Hebei province was in a low-low cluster area, and Xinjiang Uyghur Autonomous Region, Yunnan province, and Guangdong province were all in low-high cluster areas. OLS spatial regression model analysis showed that regions with a higher proportion of males (β = 23.878, t = 3.207, P = 0.003), a higher proportion of individuals aged 0 – 14 years (β = 0.751, t = 3.665, P < 0.001), a higher proportion of individuals aged 15 – 64 years (β = 0.929, t = 3.279, P = 0.003), a higher illiteracy rate (β = 0.675, t = 2.703, P = 0.011), a higher tobacco consumer price index (β = 2.563, t = 2.384, P = 0.024), and a lower proportion of cities with smoke-free legislation (β = 0.069, t = 2.119, P = 0.034) had higher SHS exposure rates in healthcare facilities.

Conclusions SHS exposure in Chinese healthcare facilities is mainly concentrated in central-south, southwest, and northwest China. Sex ratio, the proportions of individuals aged 0 – 14 years and 15 – 64 years, illiteracy rate, tobacco consumer price index, and the proportion of cities with smoke-free legislation are the main influencing factors of SHS exposure in healthcare facilities in China.