A driving assist device is provided, which includes a processor configured to execute an inference module to infer that a timing of a line-of-sight movement or blink detected by a camera near a predicted timing is a timing of a recognizing action of a driver for a subsequent travel segment of a plurality of travel segments that constitute a traveling course of a vehicle, an information providing module to provide the driver with assisting information for the subsequent travel segment before the timing of the recognizing action inferred by the inference module, and a providing timing changing module to change a providing timing of the assisting information according to a quantity of the assisting information.