Stomata is not only an important gateway for plants to balance the relationship between photosynthesis and transpiration, but also a key structure affecting atmospheric carbon and water cycling. Analyzing the differences of stomatal traits among three life forms of trees, shrubs and herbs and two leaf habits of evergreen and deciduous plants in Fuzhou under heat island effect and their trade-off relationship with other leaf functional traits will be helpful to explore the adaptation strategies of plants in the thermal environment. We measured stomatal traits, stoichiometric traits and morphological traits of 441 plant samples in natural and semi-natural vegetation in Fuzhou City. The results showed that:(1) there were significant differences in stomatal length (SL) and stomatal density (SD) between the three life forms and the two leaf habit plants(P<0.05), but no significant differences in potential stomatal conductance index (PCI) between the three life forms and the two leaf habit plants(P>0.05). The SL of herbs was higher than that of shrubs and trees, and SD of trees was the highest, followed by shrubs and herbs. The SL of deciduous plants was higher than that of evergreen plants, but SD of deciduous plants was lower than that of evergreen plants. (2) The trade-off between SL and SD existed stably in the three life forms and two leaf habit plants, and showed different trade-off characteristics with the ecological strategies. When SL was constant, SD of trees was the largest, SD of shrubs was the smallest, and SD of evergreen plants was larger than that of deciduous plants. (3) The stomatal traits were closely related to leaf morphology and stoichiometric characteristics. SL was positively correlated with specific leaf area(SLA)(P<0.01) and negatively correlated with leaf area(LA)(P<0.01). SD was negatively correlated with leaf nitrogen content(LNC), leaf phosphorus content (LPC), SLA(P<0.01), and positively correlated with LA(P<0.01). PCI was negatively correlated with LNC and SLA(P<0.01), and positively correlated with leaf thickness(LT) (P<0.05). (4) The complex environment was an important driving factor for variation of stomatal traits. SL and PCI were negatively correlated with mean annual temperature(MAT) (P<0.05).