A touch pen includes a bush, a sliding rod, and a pen body. The sleeve has a pen head secured at an end and defines a receiving hole. The sliding rod is fixed in the receiving hole and defines a guiding slit. The pen body has an extending end defining an accommodating hole. The extending end is receivable in the receiving hole and the sliding rod is receivable in the accommodating hole. A holding pin is secured in the accommodating hole and passes through the guiding slit, the pen body slides relative to the pen head, the holding pin slides along the guiding slit and can be hold at the two ends of the guiding slit.