A method and a device for storing a computer program in a program memory of a control unit. The computer program is stored according to predefinable rules in specific memory areas of the program memory. To recognize an erroneous jump into an unused memory area of the program memory, in which the computer program is not stored, as rapidly as possible and to prevent the control unit from being in an irregular state, selectable information, through which the control unit is transferred into a defined state, is stored in the unused memory areas of the program memory, in which the computer program is not stored.