A driving assistance device for a vehicle includes: an assistance processing portion that executes a notification of a possibility of a host vehicle intersecting with an other vehicle based on host vehicle information including information that provides an estimation of a travelling course of the host vehicle and an other vehicle information including information that provides an estimation of a travelling course of the other vehicle and acquired by wireless communication; and a map acquisition portion that acquires map data including data that specifies a circular intersection. The host vehicle information includes a position of the host vehicle. The assistance processing portion prevents the notification based on the circular intersection, which is disposed in front of the host vehicle in the travelling course of the host vehicle, according to at least the host vehicle information and the map data acquired by the map acquisition portion.