An autonomous driving vehicle system which is capable of switching a driving state of a vehicle, the system comprising: a peripheral information detection unit configured to detect peripheral information of the vehicle; a traveling plan generation unit configured to generate a traveling plan along a target route set in advance on a map based on the peripheral information detected by the peripheral information detection unit and map information; a driving operation information acquisition unit configured to acquire an operation amount of a driving operation of a driver relating to at least one of a steering operation, an accelerator operation, and a brake operation of the vehicle or a duration count according to a duration of the driving operation; the system being characterized by comprising a driving state switching unit configured to, based on the operation amount or the duration count, switch among an autonomous driving state where the traveling of the vehicle is controlled using the traveling plan, a cooperative driving state where the vehicle is allowed to travel in cooperation with the driving operation based on the traveling plan and the operation amount, and a manual driving state where the operation amount is reflected in the traveling of the vehicle, wherein the driving state switching unit switches the driving state to the cooperative driving state when the driving state is the autonomous driving state and when the operation amount is equal to or greater than an intervention determination threshold value and less than a manual driving start threshold value or the duration count is equal to or greater than a first threshold value and less than a second threshold value, and when the driving state is the cooperative driving state, switches the driving state to the autonomous driving state when the operation amount is less than the intervention determination threshold value or the duration count is less than the first threshold value, and switches the driving state to the manual driving state when the operation amount is equal to or greater than the manual driving start threshold value or the duration count is equal to or greater than the second threshold value. a peripheral information detection unit configured to detect peripheral information of the vehicle; a traveling plan generation unit configured to generate a traveling plan along a target route set in advance on a map based on the peripheral information detected by the peripheral information detection unit and map information; a driving operation information acquisition unit configured to acquire an operation amount of a driving operation of a driver relating to at least one of a steering operation, an accelerator operation, and a brake operation of the vehicle or a duration count according to a duration of the driving operation; the system being characterized by comprising a driving state switching unit configured to, based on the operation amount or the duration count, switch among an autonomous driving state where the traveling of the vehicle is controlled using the traveling plan, a cooperative driving state where the vehicle is allowed to travel in cooperation with the driving operation based on the traveling plan and the operation amount, and a manual driving state where the operation amount is reflected in the traveling of the vehicle, wherein the driving state switching unit switches the driving state to the cooperative driving state when the driving state is the autonomous driving state and when the operation amount is equal to or greater than an intervention determination threshold value and less than a manual driving start threshold value or the duration count is equal to or greater than a first threshold value and less than a second threshold value, and when the driving state is the cooperative driving state, switches the driving state to the autonomous driving state when the operation amount is less than the intervention determination threshold value or the duration count is less than the first threshold value, and switches the driving state to the manual driving state when the operation amount is equal to or greater than the manual driving start threshold value or the duration count is equal to or greater than the second threshold value.