Laser Induced Fluorescence technique with a tunable diode laser which has central wavelength of 668.61nm was used to measure the VDF(velocity distribution function) of the Ar ion metastable state in MICP(magnetized ICP). With varying the pressure, rf power and magnetic field strength, we got the VDF, and we could get the temperature, relative density and the drift velocity of the Ar ion metastable state from the VDF. And, comparing them with electron temperature and density measured by Langmuir probe, we tried to understand the motions of the Ar ion and its metastable.