To make good use of the widely used steel-bars truss deck in assembled steel structure buildings, the bottom rebar of the steel truss was welded to the upper flange of U-shaped steel beam as a new shear connector in this study, and the experimental study and finite element analysis were conducted on four designed specimens with different shear connectors, i.e. steel truss, angle steel, studs and their combination. The test results showed that the failure modes included bending failure and slip failure; the specimen with steel truss as shear connector can not achieve the full shear connected composite beams, and some studs can be configured to improve its composite action. The shear performance of the specimen with steel truss and stud as combined shear connector was better than that of the specimen with steel truss and angle steel as combined one. Then, finite element analysis was conducted via ABAQUS software, and the ultimate bending capacity of finite element analysis was in good agreement with the ex? perimental one. Based on the experimental and finite element analysis study, a calculation formula of ultimate bend? ing capacity of the U-shaped steel-concrete composite beam with truss deck under positive bending moment was de? rived based on the plasticity theory