To provide a cam type tail stock with little impact in engaging a center and a work center hole with each other while reducing the time for a work to make contact with the center by increasing the speed in the initial stage of advancement of a tail stock spindle and reducing the speed in the latter half.

This cam type tail stock comprises a cam delivery mechanism constituted of a grooved shaft attached in the rear of the tail stock spindle and on which a groove for engagement to pressurize a spring built in this tail stock spindle and to move the tail stock spindle forward and backward is engraved orthogonally with the spindle, a slider on which a projected part to be engaged with the shaft is formed on one surface and a cam groove having a groove wall surface in parallel with this groove is formed on the other surface, a guide fastened on a tail stock main body and to guide the slider to move in parallel with a shaft center of the tail stock spindle and a cam member engaged with the cam groove and to position the tail stock spindle forward and backward through the slider, and a driving member to drive the cam delivery mechanism.