PURPOSE: To provide a graphic rotating method which can deal with various partial data without increasing the processing frequency by applying the position correction to the rotated partial data so as to secure a state where the partial data are rotated at the same position.

CONSTITUTION: A calculation is carried out to return the partial data 3 to a regular position in a state where the state of figure (a) is totally rotated by 180° in a figure (b) since the data 3 is not positioned at the regular position in a buffer 2. In other words, the position is corrected in both vertical and horizontal directions. In the vertical position correction processing, the vertical correction value is added to the position data on the data 3 included in the buffer 2 set in the state of (b) and the data 3 is moved upward as shown in a figure (c). In the horizontal position correction processing, the horizontal correction value is added to the data 3 set in the state of (b) and the data 3 is moved horizontally from the state of (c) as shown in a figure (d). Thus the data 3 is set at its regular position and the 180° partial rotation processing is complete.