PURPOSE: To provide a machine tool guide system which uses laser and an optical fiber communication network to distribute an optical signal to prescribed positions on a machine.

CONSTITUTION: This controller consists of a laser source 35 which emits plural laser beams, splitters 36 and 53, a position monitor provided with means 37 and 58 which are operationally connected to plural mobile elements 34 of the machine, each of which can be moved on at least one axis, and receive the laser beam signals to generate laser signals including position information from reception signals, and a control processor 44 which processes position signals from plural elements to generate a control signal which controls the position of each element. Optical fiber networks 40 and 50 transmit laser beam signals from the laser source to respective elements and transmit position-modulated laser beam signals from elements to the control processor.