Abstract: Spatial shell elements and solid elements were adopted to simulate steel plates and the concrete deck of a composite curved beam; also spring elements with 3-dimension displacement were used to simulate each stud of the composite beam. Based on actual work, the mechanical behavior of a composite curved beam with open sections was calculated by the finite element method, and the stud shear distribution in the composite curved beam was obtained. The studs in the composite curved beam not only burden tangential shear forces but also burden normal shear forces, where the tangential shear forces are large at the ends of the beam and small in the mid-span along the beam length, and the normal shear forces are large in the mid-span and small at the beam ends along the beam length. When the ratio of the arc length of the central line in the curved beam to the radius of the arc is less than 0.5, it is feasible to substitute the stud tangential shear force for its resultant shear force approximately and neglect the component of the normal shear force. The arrayed Multi-row studs along the length of the curved composite beam, the non-uniformity of shear forces exists in the both inner row and outer row stud of the same section, and the shear force in the outer row stud is larger than that of in the inner row stud. The degree of the non-uniformity is increased by increasing the ratio of the arc length of the central line in the curved beam to the radius of the arc, which is worthy of enough attention in design.