Abstract: A handwritten data input device comprises a coordinate detection tablet for detecting handwritten data input by handwriting with an input pen, and a program recording medium therefore, and is characterized in that, merely as a particular symbol such as a check mark is input by handwriting to an input region of the tablet, the handwritten data can be converted into a category code corresponding to the particular symbol, for each and every input region on the tablet. The category codes which indicates the meanings of the respective marks are stored in the RAM while the particular marks are associated with the respective handwriting marking boxes on a marking sheet. When a mark is handwritten in a marking sheet on the tablet, the CPU searches the contents of the RAM on the basis of the written mark, and converts it into a corresponding category code.