A vehicle control system based on height of obstacle, characterized in that the vehicle control system comprising an acquisition unit, a processing unit and an execution unit, the execution unit comprises an alarm module; the acquisition unit comprises at least one group of detection modules arranged at a front of a vehicle; each group of detection modules comprises a first range radar (3, 4) arranged on a front roof of the vehicle and a second range radar (1, 2) arranged right at a front of the vehicle vertically below the first range radar (3, 4); the first range radar (3, 4) and the corresponding second range radar (1, 2) are both configured to detect an area in front of the vehicle and the detection areas are partially overlapping; the processing unit judges a height and distance between the vehicle and an obstacle according to obstacle information detected by the range radars; if the obstacle is detected by only one range radar in one group of detection modules, the height difference between the obstacle and the top end of the vehicle or the distance between the obstacle and the front end of the vehicle are calculated based on an obstacle distance detected by the range radar; and when the height difference between the vehicle and the obstacle or the distance between the obstacle and the front end of the vehicle is less than a safety distance, the alarm module in the execution unit is controlled to give an alarm; characterized in that if the obstacle information is detected by both the first range radar (3, 4) and the second range radar (1, 2) belonging to the same group of detection modules, a position relationship between the obstacle and the vehicle is calculated according to the obstacle detected in an overlapping detection area; an included angle (α) between a straight line from the obstacle to the second range radar (1, 2) and a vehicle front plane is calculated by using the law of cosine according to a height difference of an installation distance (h) between the first range radar (3, 4) and the second range radar (1, 2) in the group and an obstacle distance detected by the two range radars; then a height difference between the obstacle and a top end of the vehicle is determined; if the height difference does not change suddenly in two periods before and after, the obstacle is located in the overlapping detection area; when the height difference >0, the obstacle is higher than the top end of the vehicle, when the height difference <0, the obstacle is lower than the top end of the vehicle. if the obstacle is detected by only one range radar in one group of detection modules, the height difference between the obstacle and the top end of the vehicle or the distance between the obstacle and the front end of the vehicle are calculated based on an obstacle distance detected by the range radar; and when the height difference between the vehicle and the obstacle or the distance between the obstacle and the front end of the vehicle is less than a safety distance, the alarm module in the execution unit is controlled to give an alarm; characterized in that if the obstacle information is detected by both the first range radar (3, 4) and the second range radar (1, 2) belonging to the same group of detection modules, a position relationship between the obstacle and the vehicle is calculated according to the obstacle detected in an overlapping detection area; an included angle (α) between a straight line from the obstacle to the second range radar (1, 2) and a vehicle front plane is calculated by using the law of cosine according to a height difference of an installation distance (h) between the first range radar (3, 4) and the second range radar (1, 2) in the group and an obstacle distance detected by the two range radars; then a height difference between the obstacle and a top end of the vehicle is determined; if the height difference does not change suddenly in two periods before and after, the obstacle is located in the overlapping detection area; when the height difference >0, the obstacle is higher than the top end of the vehicle, when the height difference <0, the obstacle is lower than the top end of the vehicle.