Based on bilateral trade data between China and 18 major trading partners from 2005 to 2023, this study employs an extended trade gravity model to examine the impact of geopolitical risk (GPR) on China’s trade. The results show that GPR has a significantly positive effect on trade volume (coefficient: 0.197), which remains robust after replacing the dependent variable with unilateral export volume. Heterogeneity analysis reveals that GPR promotes trade more strongly for developing countries (coefficient: 0.264) than for developed countries, where the effect is weak and insignificant. Mechanism analysis indicates that geopolitical risk affects trade through higher transaction costs, policy uncertainty, and weakened market confidence, while bilateral political relations and regional trade agreements (e.g., RCEP) can partially buffer these effects. The findings provide empirical support for understanding the role of non-economic factors in global trade and offer policy implications for China’s trade optimization under the “dual circulation” strategy.