The cooling and humidifying effect of the urban plant community plays an important role in alleviating the"urban heat island effect".To study the effect of vegetation in regulating urban microclimate at a small scale,arboreal forest,shrubs and lawns were chosen in Mailu campus of Jiangxi Finance and Economics University.The results showed that:(1)The most significant cooling effect of arboreal forest occurred at 20:00(-4.00 ℃),while the weakest effect occurred at 10:00(-1.68 ℃).The most significant cooling effect of shrubs occurred at 8:00(-2.95℃),while the least effect occurred at 12:00(-0.27 ℃).The most significant cooling effect of lawns occurred at 20:00(-2.31 ℃),while the least effect occurred at 10:00(0.38℃).(2)In morning,the cooling and humidifying effects of shrubs were great,and the humidifying effects of lawns were significant.In afternoon,the cooling effect of lawns and the humidifying effect of arboreal forest varied greatly.(3)The cooling and humidifying effects of arboreal forest,shrubs and lawns decreased as the distance increased.The changes in temperature difference were consistent with the variation in relative humidity difference at the horizontal and vertical direction.