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[Display omitted] • The new ground motion prediction model can capture the nonlinear mean effect of soils in the capital circle region of China. • Our ground motion prediction model can predict the observed ground motions in this region. • The regional variability of ground motion is caused by the difference in anelastic attenuation and site response. • The regional differences in the anelastic attenuation at rock sites decrease with increasing periods. • GMPMs developed using data from different magnitude ranges within the same region should not be used interchangeably. Based on strong motion and seismic velocity records from small-to-moderate earthquakes in the capital circle region of China, we developed a new ground motion prediction model (GMPM) that incorporates magnitude, geometric attenuation, anelastic attenuation, and linear/nonlinear site response terms. The GMPM was subjected to evaluation through residual analysis. We compared the median predictions of the GMPM with those of two commonly used local GMPMs, as well as the observed ground motions in this region. Furthermore, we conducted an investigation into the differences between the GMPM and four NGA-West2 models. Additionally, we explored certain model parameters that could potentially explain these differences. The results indicate that the GMPM effectively captures the magnitude-dependent attenuation and nonlinear average effect of soil sites. The GMPM demonstrates the capability to predict horizontal peak ground acceleration (PGA), peak ground velocity (PGV), and spectral acceleration (SA (T = 0.01–3.0 s)). The model is applicable for surface wave magnitudes (M S = 3.1–5.1), hypocentral distances (R hyp = 10–200 km), and V S30 = 103–1070 m/s in the capital circle region of China. There are significant differences in anelastic attenuation at rock sites between southern California and the capital circle region of China. These differences decrease with increasing periods and largely diminish in far sources and soil sites. This is primarily because the effect of anelastic attenuation is neutralized by the greater site amplification of ground motion in southern California, especially over medium and long periods. The difference in ground motion observed in small-to-moderate earthquakes across different regions is predominantly influenced by long-distance attenuation and dissimilarities in site responses. [ABSTRACT FROM AUTHOR]