A method of controlling an automobile, comprising: a driver incapacitation determination step of performing a determination as to whether a driver of an automobile is incapacitated; an SOS switch operation determination step of performing a determination as to whether an SOS switch is turned on by an occupant including the driver of the automobile; a parking brake switch operation detection step of detecting an operation state by the occupant of a parking brake switch configured to operate a parking brake of the automobile; characterised by a first deceleration step of decelerating the automobile at a first deceleration using a braking mechanism when detecting that the parking brake switch is turned on in the parking brake switch operation detection step regardless of the determination in the driver incapacitation determination step and the determination in the SOS switch operation determination step while the automobile runs; a second deceleration step of decelerating the automobile at a second deceleration that is smaller than the first deceleration using the braking mechanism when not detecting that the parking brake switch is turned on in the parking brake switch operation detection step and determining that the driver is incapacitated in the driver incapacitation determination step regardless of the determination in the SOS switch operation determination step while the automobile runs; and a third deceleration step of decelerating the automobile at a third deceleration that is smaller than the first deceleration using the braking mechanism when determining that the SOS switch is turned on in the SOS switch operation determination step, detecting that the parking brake switch is changed from on to off in the parking brake switch operation detection step, and not determining that the driver is incapacitated in the driver incapacitation determination step while the automobile runs. a driver incapacitation determination step of performing a determination as to whether a driver of an automobile is incapacitated; an SOS switch operation determination step of performing a determination as to whether an SOS switch is turned on by an occupant including the driver of the automobile; a parking brake switch operation detection step of detecting an operation state by the occupant of a parking brake switch configured to operate a parking brake of the automobile; characterised by a first deceleration step of decelerating the automobile at a first deceleration using a braking mechanism when detecting that the parking brake switch is turned on in the parking brake switch operation detection step regardless of the determination in the driver incapacitation determination step and the determination in the SOS switch operation determination step while the automobile runs; a second deceleration step of decelerating the automobile at a second deceleration that is smaller than the first deceleration using the braking mechanism when not detecting that the parking brake switch is turned on in the parking brake switch operation detection step and determining that the driver is incapacitated in the driver incapacitation determination step regardless of the determination in the SOS switch operation determination step while the automobile runs; and a third deceleration step of decelerating the automobile at a third deceleration that is smaller than the first deceleration using the braking mechanism when determining that the SOS switch is turned on in the SOS switch operation determination step, detecting that the parking brake switch is changed from on to off in the parking brake switch operation detection step, and not determining that the driver is incapacitated in the driver incapacitation determination step while the automobile runs.