The cement hydration heat in the operation period have disappeared，the structure in a more stable state because of temperature，the outside temperature changes will cause the aqueduct internal temperature stress changes，at the same time in the sunshine，environmental temperature changes and sudden cooling structure caused by temperature stress and temperature difference change.The establishment of three-dimensional model of Kezi river aqueduct by 3D finite element simulation software，aqueduct period，temperature and period of running stress distribution，finally effectively crack in the aqueduct during operation，in order to provide the basis for future design of aqueduct design.