Forest soil plays an important role in atmospheric methane uptake, the rate of which is affected by soil water content and precipitation change. In this study, we excluded precipitation by 20% and 60% in a Cunninghamia lanceolate plantation to analyze how precipitation reduction affects soil methane uptake in subtropical China. The results showed that soil water content changed significantly in precipitation exclusion treatments, with an annual mean value of 18.87%, 23.89%, and 28.33% in 60% precipitation exclusion, 20% precipitation exclusion, and control treatments, respectively. We also found V_CH4 had strong and substantial fluctuations in the study year, with the highest rate hit in August (control 75 μg m^-2 h^-1) and the minimum in February (control 10.93 μg m^-2 h^-1). Annual flux of soil CH₄ uptake was 2.48 kg hm^-2 a^-1 in the control treatment, and increased by 44% and 19% in the 60% and 20% precipitation exclusion treatments, respectively. Precipitation exclusion may also alter the relationship of V_CH4 and environmental factors. We found a negative correlation between V_CH4 and soil water content (P=0.001), and a weak relationship between V_CH4 and soil temperature in the control treatment. However, the relationship between V_CH4 and soil temperature became stronger after precipitation exclusion (P=0.006 at 60% precipitation exclusion and P=0.034 at 20% precipitation exclusion), and no significant correlation was found between V_CH4 and soil water content in both precipitation exclusion treatments. Our results suggest that precipitation decline may not only increase soil methane uptake in subtropical forests with global climate change in the future, but it may also change the main determining environmental factor of soil methane uptake rate from soil water content to soil temperature.