The invention discloses a tool pen telescopic structure. The tool pen telescopic structure comprises a pen head rod, a pen core, a pen head and a connector, wherein the pen head rod is arranged in a pen container; the pen core is inserted into the pen head rod; the core end of the pen core penetrates into a spring; after sleeving the core end of the pen core, the pen head is screwed up with one end of the pen container through threads; one end, with an insertion slot, of the pen head rod is connected with the pen head; the connector passes through a slot position on the pen container, and is inserted into the insertion slot in the pen head rod; a pen cover is arranged on the pen head; and a rubber ring is arranged in a pen hole for allowing the pen core to get in and out in the pen head. According to the tool pen telescopic structure disclosed by the invention, the slot position of the pen container is opened, closed and locked, and telescopic length of the pen head is regulated, so that use is very convenient.