The objective of the present invention is to achieve a measured data synchronizing system and a measured data synchronizing method which can determine the measured data whose synchronization is secured among measuring units without being restricted by the number of measuring units in the measuring part. The writing instrument includes an outer barrel, a lead feeding mechanism disposed in the outer barrel, and a stick-shaped material propelling mechanism connected to a rear portion of the lead feeding mechanism, a female thread is formed on an inner peripheral surface of a rear portion of a lead tank of the lead feeding mechanism. In this way, the power consumption of the connector is reduced.