A study is conducted on the issue of whether lateral constraints are set on the steel truss cantilever bridge crane track beams of a heavy- cargo bridge.ANSYS finite element method is used for comparative analysis with and without supports.It is found that although the setting of lateral supports increased the Z-direction deformation of the bridge crane track beams.The overall deflection difference of the double-sided track beams is reduced,the local stress of the track beams is reduced to 17 MPa.The safety reserve under the yield strength of the steel is increased by about 7%,so that the bridge crane can operate safely on a larger scale.The conclusions indicate that under the same working conditions,the setting of supports can ensure the safe operation of bridge cranes at the same position.At the same time,this calculation result has reference significance for engineering design.