Abstract: A driving assistance device and a driving assistance method capable of decelerating a vehicle in the event of an emergency while suppressing erroneous operations of an occupant are provided. A driving assistance device may include a first switch configured to receive an operation of an occupant, a second switch configured to receive an operation of the occupant after the first switch receives an operation of the occupant, a storage configured to store information, and a processor configured to execute a program stored in the storage, wherein the storage stores the program that causes the processor to execute, a process of decelerating a vehicle until the speed of the vehicle becomes smaller than a predetermined speed when the second switch receives an operation of the occupant.