Changes in global warming are expected to have profound effects on precipitation. Root production plays a key role in ecosystem carbon, nutrient, and water cycling; however, the response of root production to soil warming and precipitation exclusion is not well understood. The aim of this study was to explore the below-ground responses and adaptability of the most important timber species in southern China, Chinese fir (Cunninghamia lanceolata), to global warming and precipitation changes. A factorial experiment of soil warming (ambient, +5℃) and precipitation exclusion (ambient, -50%) was carried out in the Chenda State-owned Forest Farm in Sanming, Fujian Province. We measured changes in fine root production (fine root birth) after one year of soil warming and precipitation exclusion using the mini-rhizotron method. Results of two-way analysis of variance (ANOVA) showed that soil warming and precipitation exclusion had no significant effect on the total number of fine roots produced, whereas their interaction had a marked effect on the total number of fine roots produced. Compared to the control plots, the total number of fine roots produced increased significantly in the warmed soil plots, but decreased significantly in the warmed soil plus precipitation exclusion plots compared to the warmed plots and the precipitation exclusion plots, respectively. Repeated-measures ANOVA including soil warming, precipitation exclusion, and season showed that the interaction of soil warming and season, and the interaction of precipitation exclusion and season had significant effects on the number of fine roots produced. Compared to the control plots, the number of fine roots produced increased significantly in the warmed soil plots in the spring, and in the precipitation exclusion plots in the autumn, but decreased significantly in the warmed soil plus precipitation exclusion plots in the summer and winter. These results indicate that soil warming, precipitation exclusion, and their interaction influence the season of fine root production. A three-way ANOVA including soil warming, precipitation exclusion, and diameter class showed that the interaction of soil warming precipitation and diameter class had a significant effect on the number of fine roots produced, which was significantly higher in the soil warming treatment than in the control at 0-1 mm. However, the number of fine roots produced was significantly lower in the soil warming plus precipitation exclusion treatment than in the precipitation exclusion treatment and soil warming treatment, respectively. These results indicate that the effect of the interaction of soil warming and precipitation exclusion on the number of fine roots produced mainly occurred at 0-1 mm. The three-way ANOVA including soil warming, precipitation exclusion, and soil layer showed that the three-way interaction had no effect on the number of fine roots produced. Only the precipitation exclusion treatment resulted in a significantly higher number of fine roots than the control in the soil layer of 20-40 cm. This suggests that the interaction of soil warming and precipitation exclusion on the number of fine roots produced had similar effects at different soil layers. It is concluded that the interaction of soil warming and precipitation influenced root production through changing the fine root seasonal distribution and diameter class allocation, which may play important roles in the growth of Chinese fir.