Abstract: In order to estimate the capacity of right-turn lane at signalized intersections with channelized islands.Based on the gap acceptance model,this paper proposes a new approach to calculating the capacity of right-turn lane at signalized intersections with channelized islands.This model takes into account the interference of non-motorized traffic enter channelized islands.The non-motorized traffic is treated as the traffic on the major road-a crosswalk,which has great impacts on right-turn vehicles on the minor road-an exclusive right-turn lane.The basic model is modified by introducing the red light effect adjustment coefficient.The new model is calibrated and tested using the field data collected at 6 signalized intersections with channelized islands in 4 cities.The average relative error between the calculated value and the observed is 9.28%,which means the proposed method in this paper can better estimate the capacity of an exclusive free right-turn lane under the interference of non-motorized traffic.