Abstract: This study investigated the effects of sex and leaf morphology on photosynthetic capacity, energy allocation, and dissipation in Sabina chinensis (L.) Ant. The experimental materials included prickly and scaly leaves from female, male, and monoecious plants. Gas exchange parameters, chlorophyll fluorescence characteristics, and non-structural carbohydrate (NSC) content were measured. Results showed that prickly leaves from both female and male plants exhibited significantly higher photosynthetic rate (P_n), the transpiration rate (T_r), the stomatal conductance (G_s), water use efficiency (WUE), and NSC compared to scaly leaves. Similarly, the non-photochemical quench (NPQ) and the ability of PSⅡ reaction center to trap energy from antenna pigment (1/F_o−1/F_m) were significantly higher in male and female prickly leaves, while maximum photochemical efficiency (F_v/F_m), the electron transfer rate (ETR), actual photochemical quantum efficiency (Ф_PSⅡ), photochemical quenching (qP), the highest maximum relative electron transfer rate (rETR_max), and half-saturated light intensity (I_k) were significantly lower in male and female prickly leaves compared to scaly leaves. Among sexes, female plants demonstrated significantly higher P_n, NSC, NPQ, and 1/F_o−1/F_m than male plants, while F_v/F_m, ETR, qP, rETR_max, and I_k were significantly lower in females. Correlation analysis showed a strong positive correlation between NSC and both P_n and 1/F_o−1/F_m, but a strong negative correlation between NSC and ETR. In conclusion, prickly leaves adapt to high-light environments by improving light energy capture ability and heat dissipation ability, whereas scaly leaves adapt to low-light environments by improving light energy utilization efficiency and light protection mechanisms. The coexistence of prickly and scaly leaves allows S. chinensis to meet the demands for photosynthate production and adapt to varying light conditions during growth and development. Female plants, through higher P_n, achieve greater NSC content, supporting the requirements for reproduction and growth.