Thiazolidinedione compound crystalline forms useful as a bulk material for the manufacture of a peroxisome proliferator-activated receptor (PPAR) γ activator or an anticancer pharmaceutical composition are provided, which are hydrate crystalline forms of 5-(4-{[6-(4-amino-3,5-dimethylphenoxy)-1-methyl-1-H-benzimi dazol-2-yl]methoxy}benzyl)-1,3-thiazolidine-2,4-dione represented by Formula (I) below and of its dihydrochloride.