Abstract: In this study, the calculation method of capacity of shared lanes at signalized intersection was presented. The blocking conditions of shared lanes were analyzed. Taking the shared lane with right-turn movement as an example, a mathematical model was proposed for an exact calculation for the capacity of shared lanes. Combined with field survey data and VISSIM simulation, the accuracy and adaptability of the model were analyzed. The results indicate the validity of the principle of the model which takes into account various factors that affect the capacity of shared lanes at signalized intersections, and makes calculated results closer to reality.