This invention provides an inorganic scintillator capable of producing scintillation by radiation, which is a crystal comprising metal oxides including Lu, Gd, Ce and Si, which satisfies the condition specified by the following inequality (1A): 0.0025.ltoreq.{A.sub.Ce/(A.sub.Lu+A.sub.Gd)}.ltoreq.0.025, (1A) and which has an absorption coefficient of no greater than 0.500 cm.sup.-1 for light with a wavelength of 415 nm.