In spite of high carrying capacity, it involves great difficulty to control the temperature and prevent cracking during the construction of high strength concrete aqueduct in summer because of high heat of hydration. The finite element method for unsteady temperature field and stress field is applied to simulate the construction process in summer for a typical aqueduct structure. The cause of cracking at dangerous positions is analyzed based on the calculation results of temperature field and stress field in different cases. Corresponding measures of pipe cooling and surface thermal insulation are put forward, which will be beneficial for the design and construction of such high strength concrete structure.