The effect of Urban Heat Islands (UHIs) is becoming increasingly serious in cities. Research on the adaptive planning policies for microthermal environments at the residential block level of cities is thus becoming of greater significance. Based on the cooling effect of planning control elements in residential block areas, the element effects characteristics of water bodies and vegetation distribution on the thermal environment of residential blocks were analyzed by using ENVI-met software. The simulation data analysis showed that the combination of water bodies and vegetation had a synergistic cooling effect. Based on these results, simulations of five effective adaptive measures were carried out step by step in planning scenarios, that is, improving the water bodies with vegetation corridors, the application of high-albedo material on streets, and increasing the number of green patches, east-west green corridors, and north-south green corridors. The results were as follows. First, although each of the five optimization strategies have a certain degree of cooling effect on the entire block, the superposition of each factor had a synergistic effect. Second, different spatial optimization strategies had different cooling ranges for each subzone. The optimization of the north-south green corridor, green patches, and water features corridors were particularly significant for microclimate cooling. The east-west green corridor has a certain influence on a certain range of downwind zones and had an auxiliary cooling effect. The high-albedo material also had a weak overall decrease function for the thermal environment. Finally, the downwind area of the urban creek network had a great impact on cooling intensity, with distance attenuation characteristics; it was also proposed that the comprehensive cooling effect of the green space network with optimized layout was greater than that of any single green space element. The optimization scenario planning research provided a method for improving the scientific distribution of adaptation measures in urban residential blocks.