In a driving assistance device 1, when an execution determination unit 12 determines that a driving assistance unit 11 performs driving assistance, a consciousness degradation determination unit 13 performs control such that a warning unit 9 is less likely to issue a warning than that when the driving assistance is not performed. Therefore, even when the position of a host vehicle is changed by the steering of the host vehicle by a driving assistance unit 11, it is possible to reduce the discomfort of a driver due to a warning.
