The invention provides a counter capable of displaying the length of a fishing line, wherein the length of the fishing line can be corrected by a simple operation according to the winding condition thereof.The length of the fishing line (LN) is displayed as the water depth of the fishhook assembly by the counter.The device comprises a fishing line reel control part (30) equipped with a length measurement mechanism for the fishing line and a display control mechanism, a display part (5), a switch operation part (6) equipped with a storage operation mechanism and a correction operation mechanism, and a storage part (43).The length of the fishing line is measured based on the rotation position data by the length measurement mechanism according to the relation of the rotation position data detected by a spool sensor and the length of the fishing line.The length of the fishing line is displayed on the display part by the display control mechanism.The length correction data (ALD) of the fishing line displayed on the display part is stored in the storage part by the storage operation mechanism.Then the length of the fishing line detected by the length measurement mechanism and stored in the storage part is corrected by the correction operation mechanism.
