Abstract: Based on the panel data from the regional statistical yearbook, this paper uses the non-expected output superefficiency SBM-Malmquist index model to measure the forest green total factor productivity and its heterogeneity structure in 30 provinces of China from 2008 to 2019. By constructing a nonlinear dynamic panel threshold regression model, the influence mechanism of forestry industry agglomeration on forestry green total factor productivity was analyzed from the perspective of financial support. The results show that: overall, the green total factor productivity of Chinese forestry is in a slow growth trend, but it fluctuates obviously year by year and there is regional heterogeneity. In addition, under different financial support levels, the effect of forestry industry agglomeration on forestry green total factor productivity presents nonlinear characteristics, that is, lower financial support level inhibits the positive effect of forestry industry agglomeration on the improvement of forestry green total factor productivity. However, when the financial support level increases and exceeds the critical value, the positive externalities of forestry industry agglomeration can be better utilized to promote the improvement of forestry green total factor productivity. The paper provides a new perspective and a new plan for promoting ecological civilization construction and realizing forestry modernization.