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Surface solar radiation (<i>R_s</i>) is essential to climate studies. Thanks to long-term records from the Advanced Very High-Resolution Radiometers (AVHRR), the recent release of International Satellite Cloud Climatology Project (ISCCP) HXG cloud products provide a promising opportunity for building long-term <i>R_s</i> data with high resolutions (3 h and 10 km). In this study, we compare three satellite <i>R_s</i> products based on AVHRR cloud products over China from 1983 to 2017 with direct observations of <i>R_s</i> and sunshine duration (SunDu)-derived <i>R_s</i>. The results show that SunDu-derived <i>R_s</i> have higher accuracy than the direct observed <i>R_s</i> at time scales of a month or longer by comparing with the satellite <i>R_s</i> products. SunDu-derived <i>R_s</i> is available from the 1960s at more than 2000 stations over China, which provides reliable decadal estimations of <i>R_s</i>. However, the three AVHRR-based satellite <i>R_s</i> products have significant biases in quantifying the trend of <i>R_s</i> from 1983 to 2016 (−4.28 W/m²/decade to 2.56 W/m²/decade) due to inhomogeneity in satellite cloud products and the lack of information on atmospheric aerosol optical depth. To adjust the inhomogeneity of the satellite <i>R_s</i> products, we propose a geographically weighted regression fusion method (HGWR) to merge ISCCP-HXG <i>R_s</i> with SunDu-derived <i>R_s</i>. The merged <i>R_s</i> product over China from 1983 to 2017 with a spatial resolution of 10 km produces nearly the same trend as that of the SunDu-derived <i>R_s</i>. This study makes a first attempt to adjust the inhomogeneity of satellite <i>R_s</i> products and provides the merged high-resolution <i>R_s</i> product from 1983 to 2017 over China, which can be downloaded freely.