Abstract: Running efficiency of low-quality and inefficient Pinus massoniana sparse forest improved by inter-planting Castanopsis fissa was studied. The results showed that when the canopy density of Pinus massoniana was 0.2-0.5, the inter-planted Castanopsis fissa could grow normally, and the growing amount peaked at 0.3-0.4 canopy density. By inter-planting Castanopsis fissa, the growth of Pinus massoniana was promoted, and the average dimeter, height, and stand volume were also improved, furthermore, the stand volume varied at very significant difference level, which significantly increased the productivity forest stand volume. Main environmental factors, including soil bulk density, soil water content, light intensity, air temperature, soil temperature and air relative humidity, were also changed to be helpful for growth of Pinus massoniana and Castanopsis fissa, which improved the ecological environment and the running efficiency.