PURPOSE: To obtain the dictionary registration processing device which can totally register character strings requiring registration on a dictionary later while preparing and updating a document.

CONSTITUTION: A document processor is equipped with a registering candidate designation part 11 and a registration processing part 12 and when there is a prescribed designation input, the registering candidate designation part 11 is called from a document processing part 10 and preserves position information showing a position designated by a prescribed instruction on a document displayed at a display part 3 as registering candidate position information to be added to the document. When there is the prescribed designation input, the registration processing part 12 is called from the document processing part 10 and the successively executes a dictionary registration processing for each position information held by the registering candidate position information. In the dictionary registration processing, the prescribed part of the document decided by each the position information is displayed at the display part 3 and according to the prescribed instruction, the character string designated on the displayed document is registered on a dictionary 5 as the character string having designated reading.