Abstract: To determine the relationship between the percentage of bisexual flowers and humidity-temperature factors and to provide a theoretical base for the regulation of flower sexual differentiation and blossom period, a linear correlation between bisexual flower rate of Kate mango and 55 humidity-temperature factors was established through statistical methods. Results show that Kate mango bisexual flower percentage is high and rises with temperature increase.The major differentiating anaphases of the floral organ are from 30 to 1 day before blossom. Bisexual flower percentage is influenced by daily average maximum temperature, daily average temperature, daily average minimum temperature, and daily accumulated temperature in the major differentiating anaphase of the floral organ. A positive linear correlation is found between bisexual flower percentage and daily average maximum temperature, daily average temperature, daily average minimum temperature, and accumulated daily temperature in 21～30 days, 11～15 days, and 1～5 days before blossom. A similar correlation exists between bisexual flower percentage and daily average temperature, daily average minimum temperature, and accumulated daily temperature in 6～10 days before blossom. A polynomial correlation is found between bisexual flower percentage with daily average maximum temperature, daily average temperature, daily average minimum temperature, and daily accumulate temperature in 16～20 days before blossom and daily average maximum temperature in 6～10 days before lossom,indicating that the bisexual flower percentage rises with temperature increase but decreases when temperatures go above a certain threshold. The daily average humidity in the entire differentiating anaphase influences bisexual flower percentage especially 11～20 days before blossom. Thus degeneration of the Kate mango small flower ovaries has a significant correlation with humidity-temperature conditions in differentiation,anaphase of floral organ and proper high humidity-temperature favors ovary growth and increase in bisexual flower rate.