In this study, we treated four-year-old Toona sinensis with stubble height 20 cm (T₁), 50 cm (T₂), 80 cm (T₃) and no stubble (CK) to investigate the growth of sprouting branches and leaves, as well as the changes of leaf gas exchange parameters, photosynthetic pigment content and non-structural carbohydrate (NSC) content. We analyzed the differences in growth physiological response to different stubble heights and preliminarily explored the physiological mechanism of renewing and rejuvenating regeneration of T. sinensis plants under different stubble treatments. The results showed that: (1) different stubble heights could significantly improve the sprouting ability and promote the growth of lateral branches and leaves of T. sinensis. The sprouting number and lateral branch length of T. sinensis were the highest under T₃ treatment, while the sprouting number,leaf length, leaf width, leaf area and side branch diameter reached the maximum under T₂ treatment. (2) With the increase of stubble height, the net photosynthetic rate (P_n), transpiration rate (T_r), stomatal conductance (G_s) and water use efficiency (WUE) of leaves increased first and then decreased, and reached the maximum in T₂ treatment, which significantly increased by 17.33%, 10.00%, 13.51% and 6.98% compared with CK, respectively. Different stubble heights also increased the photosynthetic pigment content of leaves, chlorophyll a, chlorophyll b, total chlorophyll contents and carotenoid content in T₂ treatment significantly increased by 18.34%, 27.07%, 21.11% and 23.05%, respectively, compared with CK. (3) The contents of soluble sugar, starch and NSC in leaves, branches and roots of T. sinensis under different stubble heights were higher than those of CK, and the increases in T₂ and T₃ treatments reached a significant level. The distribution rules of soluble sugar, starch and NSC contents in different organs of leaves, branches and roots of T. sinensis were consistent between stubble treatment and no stubble treatment, and NSC contents showed the order of leaves > roots > branches. The results indicate that different stubble heights could improve the photosynthetic capacity of T. sinensis by increasing photosynthetic pigment content and photosynthetic gas exchange parameters of leaves, and promote the accumulation and distribution of non-structural carbohydrates in different organs through priority storage strategy to adapt to the effects of stubble treatment and regulate the occurrence and growth of sprouts. The comprehensive results of this experiment showed that the regeneration of T. sinensis with stubble height 50 cm was the best for growth recovery and photosynthetic capacity.