PURPOSE: To pattern-recognize an office document which is not formatted by employing a conversational pattern recognizing means.

CONSTITUTION: An image scanner control circuit 11 is instructed to input image information through the conversational pattern recognizing means 12. Then the means 12 indicates a display control circuit 16 to display read-out image information through an image processing circuit 13. Next the means 12 gives input information to a character pattern recognizing circuit 17 and a linear graphic recognizing circuit 18, and receives resulted recognition information as a response. The recognized results available from the circuits 17 and 18 are superimposed and displayed on a display device 16a through a vector raster converting circuit 14 and a character pattern generating circuit. The recognized result obtained in such a way is accumulated on an optical or magnetic disk device 19a by an information accumulating and retrieving means 19 through the means 12. The means 19 can retrieve and refer to the accumulated in formation afterwards.