A driving assistance device: acquires presentation target information; controls a presentation of the presentation target information; calculates a recognition requisite time which is required for a driver to recognize the presentation target information when the presentation target information is presented; calculates a degree of risk which endangers a safety of the driver; calculates a given driving time according to the degree of risk which endangers the safety of the driver; and calculates a safe driving requisite time, which is a time required for the driver to drive safely, according to the degree of risk which endangers the safety of the driver. In a non-presented state of the presentation target information, when the given driving time becomes longer than a sum of the safe driving requisite time and the recognition requisite time, the driving assistance device presents the presentation target information.