A driver assist apparatus includes: an information acquisition section that obtains a detected information of a different vehicle driving; a calculation section that calculates a risk estimation value representing a level of risk imposed on the subject vehicle by the different vehicle; a selection section that selects driver assist content corresponding to the risk estimation value; and a merging determination section that determines whether the different vehicle cuts into the expected course. Driver assist corresponding to the different vehicle cutting into the expected course is performed earlier than driver assist corresponding to a preceding vehicle driving on a lane on which the subject vehicle drives.