For the bearing capacity design of RC crane beams, the crane load action partial coefficients are determined by engineering experience for lacking the probability models of the crane load and combination actions. So the design reliability level of the beams is unknown. For the bending and shearing capacity design method of the RC crane beams, the probability model and the statistical results of crane load were introduced, and the design reliability indicators were calibrated with the basic variables non-dimension. The design reliability indicators were 5.79 and 5.87 respectively for the one and two-way bending design, and 5.31 for the oblique section shear design. The reliability index was high and conservative for the bearing capacity design of the crane beams. It quantitatively analyzed the different influence of each factors on the reliability of the crane beams, and gave some reasonable suggestions for the design and maintenance.