PURPOSE: To obtain a measuring equipment of a current density distribution of an ion beam which enables the execution of measurement in a short time and the attainment of the distribution by simultaneous measurement.

CONSTITUTION: In the equipment for measuring a current density distribution of an ion beam which is cast on a base 5 from an ion source 1, a base holding mechanism 3 holding the base 5 is provided rotatably so that it faces the ion source 1, and an ion sensor 7 which is made to face the ion source 1 and detects the current density of the ion beam at a plurality of places in longitudinal and lateral directions is provided on a side of the base holding mechanism 3 being different from a base holding side 6 whereon the base 5 is held.