There is more reaction heat of layer curing during fabrication process, so the integral SL System has shrinkage deformation. To improve the building accuracy of integral SL System, the deformation of integral SL is analyzed, a little deflection temperature stress bending differential equation, which describe the relationship of deformation with other parameters in integral SL System, is established with elastic mechanics. The relationship of distortion deformation with layer thickness, contract rate of resin, temperature difference and locations is obtained through the equation. The deformation of a bridge model is simulated with ANSYS software in different building condition. In the simulation process, curing units are activated layer by layer with the method of elements birth and death. The simulation results are in good agreement with the equation. The research results lay a foundation for building high accuracy objects with integral SL System.