A scintillator crystal represented by the following general formula (1). Ln.sub.(1-y)Ce.sub.yX.sub.3:M (1) wherein Ln.sub.(1-y)Ce.sub.yX.sub.3 represents the chemical composition of the matrix material, Ln represents one or more elements selected from the group consisting of rare earth elements, X represents one or more elements selected from the group consisting of halogen elements, M is the constituent element of the dopant which is doped in the matrix material and represents one or more elements selected from the group consisting of Li, Na, K, Rb, Cs, Al, Zn, Ga, Be, Mg, Ca, Sr, Ba, Sc, Ge, Ti, V, Cu, Nb, Cr, Mn, Fe, Co, Ni, Mo, Ru, Rh, Pb, Ag, Cd, In, Sn, Sb, Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl and Bi, and y represents a numerical value satisfying the condition represented by the following inequality (A): 0.0001.ltoreq.y.ltoreq.1 (A).