According to the present invention, a crystal of reduced glutathione having a reduced content of impurities, particularly L-cysteinyl-L- glycine and a method for producing the same are provided. The present invention relates to a crystal of reduced glutathione, wherein, in a high-performance liquid chromatography (HPLC) analysis, the peak area of L-cysteinyl-L-glycine is 0.02 or less with respect to the peak area of reduced glutathione which is taken as 100. Figure 1