Objective This study aimed to investigate the effects of two signals,H2O2 and NO,on flowering and FT gene expression in off-season longan.Method Nine-year-old off-season longan‘Shixia’was used as the experimental material and sprayed with signal promoting agent and blocking agent to analyze the dynamic changes of flowering and FT gene expression level. Result The expression level of FT gene in off-season longan increased during the flowering process,and the expression level of FT gene in leaves reached the peak earlier than that in terminal buds. SNP and MV treatments improved FT gene expression in varying degrees. DMTU and L-NNA treatments effectively inhibited FT gene expression in terminal buds,but the inhibitory effects on FT gene expression in leaves were not significant at late stage of flower bud differentiation. Conclusion According to the flowering performance of longan,H2O2 and NO play an important role in promoting and accelerating longan flowering. Objective This study aimed to investigate the effects of two signals, H2O2 and NO, on flowering and FT gene expression in off-season longan. Methy Nine-year-old off-season longan ’Shiaia’was used as the experimental material and sprayed with signal promoting agent and blocking agent to analyze the dynamic changes of flowering and FT gene expression level. Result The expression level of FT gene in off-season longan increased during the flowering process, and the expression level of FT gene in leaves reached the peak earlier than that in terminal buds. SNP and MV treatments improved FT gene expression in varying degrees. DMTU and L-NNA processed substantially disabled FT gene expression in terminal buds, but the inhibitory effects on FT gene expression in leaves were not significant at late stage of flower bud differentiation. Conclusion According to the flowering performance of longan, H2O2 and NO play an important role in promoting and accelerating longan flowering.