Abstract: In an input pen for transmitting to a tablet 19 information of variation in writing pressure as well as information of designated positions, a joint 10 is mounted on the rear end of a shaft a writing tip 12. A movable magnetic core 9 is attached to the joint 10. A push rod 13 is passed in the pen body in such a manner that longitudinal position of the push rod is controllable, with a resilient member 11 interposed between the push rod 13 and the joint 10. Longitudinal position of the push rod 13 is adjusted in order to control the load upon mounting of the resilient member 11. It is thus possible to control the load upon mounting of the resilient member 11 biasing the writing tip 12 forward by adjusting the position of the push rod 13, whereby the resilient member 11 can be mounted constantly under a predetermined load independently of variation in dimensions of components. A reliable detection of writing pressure applied to the writing tip 12 by operator's hand is therefore made possible.