PURPOSE: To realize display of an optional screen image without detectiorating the availability of a large capacity memory, by securing an area of variable length to store the screen format data on single screen.

CONSTITUTION: A screen format data storing means 11 sets the pointer value showing the head position of a first storing area 31 to a pointer 21 of a control record 2 after the screen format data of a screen number '1' to be stored in a large capacity memory 14 is applied from a host computer 7. Then the format data of the screen number '1' is set at the position where said pointer is set. When storage of the data is through, an end code 41 is written. Then a screen number '1' to be displayed on a display device 15 is received from the computer 7 via a communication circuit 8. The number 'i' is received by a terminal equipment 1 and the data obtained from the head position indicated by a pointer 2i of the code 2 stored in the memory 14 through display of the following first end code are read by a reading means 12 as the data of the number '1' and delivered to a screen format data display means 13. Thus a screen image corresponding to the screen format data of the number '1' is displayed on the screen of the device 15.