An autonomous driving trajectory determination device that is configured to determine an autonomous driving trajectory of a vehicle is configured to include: a standard trajectory generation unit configured to generate a standard trajectory for the autonomous driving of the vehicle; a moving object behavior detection unit configured to detect a behavior of a moving object; a deviating moving object detection unit configured to detect a deviating moving object that deviates from a standard state set in advance based on the behavior of the moving object and the map information; a number-of-deviating-moving objects calculation unit configured to calculate the number of deviating moving objects, which is the number of deviating moving objects interfering with the standard trajectory; and a trajectory determination unit configured to determine whether or not to set the standard trajectory as the autonomous driving trajectory based on the number of deviating moving objects.