The present invention provides a crystal of 2-[4-(2,2-dimethylpropoxy)-3-(1H-1,2,3,4-tetrazole-1-yl)phenyl]-4-methyl-1,3-thiazole-5-carboxylic acid, said crystal being useful as a therapeutic agent or a prophylactic agent for gout, hyperuricemia, and the like.本發明係提供一種有用於作為痛風、高尿酸血症等的治療藥或預防藥的2-[4-(2,2-二甲基丙氧基)-3-(1H-1,2,3,4-四唑-1-基)苯基]-4-甲基-1,3-噻唑-5-羧酸之結晶。