Based on the field observation, the dynamics of temperature and humidity at underlying surface in Beijing City and their causes were analyzed. In order to identify the spatial distribution of heat and humidity in different urban landscapes and to evaluate their influences on the urban environment quality, 5 sites including Xidan, the commercial center of Beijing district, Mudanyuan, the residential area, Kunming Lake in Summer Palace, the water body, Chaoyang park, the urban green space and Wenquan Village, the suburb of Beijing were investigated from December, 2007 to February, 2008. The temperature and humidity at underlying surfaces, such as road, green space, water body and building space in these 5 sites were monitored simultaneously in 10 h period. The results indicate: (1) the temperatures of underlying surfaces in different landscapes were in the order of the suburb < the water body < the green space < the residential area < the commercial center, while the humidities of underlying surfaces were in the opposite order. (2) Taken the suburb village as a control, the different intensities of temperature and relative humidity at 14:00 were different significantly at 0. 01 level in four types urban land. Both the commercial center and the residential area had the urban heat island and urban dry island effect obviously. The biggest different intensities of temperature and humidity between commercial center and suburb were 6.3℃ and 24.2% respectively, and those in the residential area and suburb arrived at 5.9℃ and 25.9%. (3) The daytime temperature at each sampling site varied with different underlying surfaces in the order of the water body < the green space < the building < the cement road, while daytime humidities at each sampling sitefall in the opposite order. Compared with the cement road surface, the building, green space and water body can decrease temperature and increase humidity. The results in this study may provide sound basis for urban ecological planning, environment improvement and afforestation management.