Based on the actual engineering case, the schemes of channel structure, box culvert structure and construction methods in the overall design of fabricated precast box culvert channel are compared and selected. The design of main structure, material, joint, waterproof drainage, hoisting, assembly, standard and reinforcing bar of the box culvert structure is briefly introduced. Through Midas Civil 2019 finite element calculation software, it is obtained that the calculation and analysis of the bending moment, shearing force, crack, local bearing and anti-floating subgrade bearing capacity of this box culvert can meet the standard requirements. The design effect has some referring value for the similar projects.