PURPOSE: To successively attain the unmanned execution of plural programs by realizing the load function of the program by an outside program loader device provided as the outside device of a computer, and allowing this outside program loader device to have the successive execution management function of the program.

CONSTITUTION: An outside program loader device 13 reads out program execution schedule information 15 preliminarily defined and stored in an auxiliary storage device 14, reads out a program A from the auxiliary storage device 14, and loads it to a main storage device 11 of a computer. Then, the execution condition of the program is set, and the execution starting command of the program is outputted. Afterwards, at the time of detecting the completion of the execution of the program A, a program execution stopping command is outputted. Then, when the execution schedule of the program execution schedule information 15 is not completed, the program B is loaded based on the program schedule information 15, instead of the program A.