Based on the data of daily average temperature, wind speed and relative humidity of 2093 national surface meteorological stations in China from 1961 to 2023, this study investigated the spatiotemporal distribution patterns of climate comfort days, as well as the characteristics and relative contributions of influencing factors in China. The results showed that from 1961 to 2023, the national average climate comfort days in China was 186.9 days, showing a significant increasing trend at a rate of 2.9 days per decade, with no apparent interdecadal turning point in the variation of climate comfort days. In terms of spatial distribution, the annual climate comfort days in central and eastern China show a north-to-south increasing trend, with more comfort days occurring in summer and autumn than that in winter and spring. Over the past six decades, an "overall enhancement with localized weakening" pattern was found in climate comfortability over China. Most regions experienced an increase in comfort days, particularly in northern China, where the growth was especially pronounced. The most significant increase occurred in the Northwest region, reaching 4.2 days per decade. However, decreases occurred in central and southern South China and parts of southern Hunan and Jiangxi. This has weakened the spatial distribution difference of comfort days in central and eastern China, which used to be "more in the south and less in the north". Seasonally, the comfort days from July to September in China showed a downward trend, while other months increased significantly. This inconsistent monthly variation led to a gradual reduction in seasonal differences in climate comfort, transforming China's climate comfort pattern from "summer advantage and winter inferiority" to a "increasingly balanced seasonal distribution". Regarding influencing factors, the national average temperature had increased significantly(0.3℃/10a), while the relative humidity and wind speed had decreased significantly (-0.4%/10a and -0.1 m/s/10a, respectively). The change in average temperature plays a dominant role (62%) in the change of comfort days, the change in average wind speed was the second (28%), and the change in average relative humidity had the least impact (10%). Therefore, the significant increase in annual comfort days was mainly attributed to the rise in average temperature. The decrease in comfort days in the central and eastern regions in summer was mainly affected by temperature and wind speed, while the decrease in comfortable days in most areas south of the Yangtze River in autumn was influenced by the combined effects of temperature, relative humidity and wind speed.