Roots of Nymphoides peltata collected from Lake Taihu were cultured under three different temperatures (28,30, 32℃).The biomass under such different temperature conditions were 0.0019±0.0002,0.0021±0.0003 and 0.0020±0.0003 g (DW)/cm²,respectively.Meanwhile,the dry weight of stem and root was maximum under 30℃ than other treatments that had significant difference;the order of the dry weight and biomass per unit area of leave was 30℃ > 28℃ > 32℃.Light response curves and ACI curves were determined by a Li-6400 portable photosynthesis analysis system,and the non-rectangular hyperbolic method was used to fit the curve to obtain relevant photosynthetic parameters.The results showed that the influences of temperature on order of N.peltata photosynthetic capacity was 30℃ > 32℃ > 28℃,the order of carboxylation efficiency was 32℃ > 30℃ > 28℃,transpiration efficiency and stomatal conductance showed the same trend,30℃ > 28℃ > 32℃.The photosynthetic capacity of N.peltata increased significantly with the increasing temperature,and the growth of N.peltata was promoted;however,the photosynthetic efficiency reduced when the temperature exceeded 30℃ with the suppression of N.peltata.In the appropriate temperature range(< 30℃),small amplitude warming(2℃) produced a significant effect of accumulated temperature(200℃·d), which promote the growth of N.peltata.It is deduced that the phenomenon that the average temperature of Lake Taihu increased about 1℃ during 1998 2006 may promote the expansion of N.peltata in Lake Taihu in recent years.