A collision avoidance assist apparatus includes: an object detection part configured to detect a second moving object that crosses ahead in a travel direction of a first moving object; an estimation part configured to estimate a relationship between a future location of the first moving object and a future location of the second moving object based on a location of the detected second moving object; and a determination part configured to determine that there is a possibility that the first moving object and the second moving object will collide with each other in a case where the second moving object is capable of passing the first moving object without colliding with the first moving object based on the estimated relationship and a relationship between the first moving object and the second moving object when the second moving object passes the first moving object satisfies a predetermined condition.