Direct shear tests were conducted on UHPC keyed epoxy joints, and a finite element analysis model was established to conduct extensive parameter analysis (including the number of keys, lateral stress, adhesive layer thickness, key height, and flush surface height, etc.). The distribution pattern of shear stress along the height direction in UHPC multiple keyed epoxy joints was revealed. Based on the shear stress distribution fitting function, a calculation formula for the shear strength reduction coefficient of UHPC multiple keyed epoxy joints was proposed. The average ratio of the calculated strength reduction coefficient to the experimental value is 93.8%.