A drunk driving prevention system comprising: a sensor module configured to, during breath-checking of a driver of a vehicle, measure alcohol content in the driver's exhaled breath; and a control module configured to: check, based on the measured alcohol content, whether the driver is intoxicated; determine whether the breath-checking is completed; and block starting of an engine of the vehicle when the driver fails the breath-checking, wherein the control module includes a check unit configured to display, via a display unit of the vehicle, alcohol test guide information in response to receiving an engine start input from the driver, and wherein the display unit is configured to display vehicle state guide information transmitted from the controller module, the vehicle state guide information including safety feature information and convenience feature information, and the display unit is configured to: stop displaying the alcohol test guide information and display the safety feature information on the display unit when the driver requests to display the safety feature information while the alcohol test guide information is displayed on the display unit; and display the convenience feature information on the display unit after the displaying of the alcohol test guide information is terminated when the driver requests to display the convenience feature information while the alcohol test guide information is displayed on the display. a sensor module configured to, during breath-checking of a driver of a vehicle, measure alcohol content in the driver's exhaled breath; and a control module configured to: check, based on the measured alcohol content, whether the driver is intoxicated; determine whether the breath-checking is completed; and block starting of an engine of the vehicle when the driver fails the breath-checking, check, based on the measured alcohol content, whether the driver is intoxicated; determine whether the breath-checking is completed; and block starting of an engine of the vehicle when the driver fails the breath-checking, wherein the control module includes a check unit configured to display, via a display unit of the vehicle, alcohol test guide information in response to receiving an engine start input from the driver, and wherein the display unit is configured to display vehicle state guide information transmitted from the controller module, the vehicle state guide information including safety feature information and convenience feature information, and the display unit is configured to: stop displaying the alcohol test guide information and display the safety feature information on the display unit when the driver requests to display the safety feature information while the alcohol test guide information is displayed on the display unit; and display the convenience feature information on the display unit after the displaying of the alcohol test guide information is terminated when the driver requests to display the convenience feature information while the alcohol test guide information is displayed on the display. stop displaying the alcohol test guide information and display the safety feature information on the display unit when the driver requests to display the safety feature information while the alcohol test guide information is displayed on the display unit; and display the convenience feature information on the display unit after the displaying of the alcohol test guide information is terminated when the driver requests to display the convenience feature information while the alcohol test guide information is displayed on the display.