【Objective】 This study assesses the potential of using Tetradium ruticarpum branch sawdust for cultivating edible mushrooms. The research is significant for extending the T. ruticarpum industry chain and expediting branch degradation. It also offers a reference for efficient utilization of T. ruticarpum branches. 【Method】 The Pleurotus citrinopileatus, known for its short cultivation cycle, was chosen as the experimental strain. The nutritional content of T. ruticarpum branch sawdust, mixed wood sawdust and cottonseed hulls was analyzed. Tests involved replacing 20% (treatment 1), 40% (treatment 2), 60% (treatment 3), 80% (treatment 4) and 100% (treatment 5) of the mixed wood sawdust with T. ruticarpum branch sawdust. The effects on agronomic traits, fungus bag substrate degradation, and economic benefits in cultivating P. citrinopileatus were examined, comparing with the mixed wood sawdust (CK1) and cottonseed hulls (CK2) formulations. 【Result】 The cellulose, hemicellulose and lignin contents of T. ruticarpum sawdust were comparable to those of mixed wood sawdust (P>0.05), but its hemicellulose and lignin contents were 39.64% and 16.55% lower than those of cottonseed hulls. Its crude protein content was 4.25 times and 1.91 times that of mixed wood and cottonseed hulls, respectively. Its carbon-nitrogen ratio was 0.24 and 0.55 times that of the two. Selenium was not detected in mixed wood. Selenium content in T. ruticarpum sawdust was 7.69 times that of cottonseed hulls. Using T. ruticarpum sawdust increased inputs but had minimal impact on mycelium germination, growth and harvest times. It accelerated post-harvest recovery, significantly boosted yield, substrate utilization and economic benefits. Higher mycelial growth rates and fungus bag survival rates of 100% were observed in treatments 3,4 and 5, with no significant differences compared to CK2 in treatments 4 and 5. Biological efficiency was higher in treatments 2, 3, 4 and 5 than that of CK2, with treatment 4 yielding the best results. However, the total fresh weight was significantly lower than that of CK2. Fruiting rate higher than CK1 and CK2 was observed in treatments 3 and 4. Substrate degradation was the highest in treatment 4, with substrate utilization at 71.88%, cellulose degradation at 78.08%, hemicellulose degradation at 86.38%, and lignin degradation at 71.18%. Treatment 4 also showed the best economic performance, significantly better than CK1, and nearly equivalent to CK2, with only 0.03 yuan lower in profit per bag. It significantly reduced inputs and improved input-output ratio. 【Conclusion】 The T. ruticarpum branch sawdust is a material richer in crude protein and selenium than mixed wood sawdust and cottonseed hulls, and can replace pure mixed wood sawdust and pure cottonseed hulls for cultivating P. citrinopileatus. Replacing 80% of the mixed wood sawdust can guarantee a good survival rate of fungal packages and also a relatively high mycelial growth rate, yield, fourth flush yield rate, high material degradation and economic performance. It is a excellent edible fungi raw material, with a specific formulation of 62.4% (mass fraction, the same below) T. ruticarpum branch sawdust, 15.6% mixed wood sawdust, 20.0% wheat bran, 1.0% lime, and 1.0% gypsum.