A solid preparation containing compound (I), wherein the definition of compound (I) is as defined in the description, and pioglitazone, which is useful as a therapeutic drug for diabetes and the like and superior in the dissolution property, chemical stability and dissolution stability, is provided. A solid preparation containing the following first and second parts: (1) the first part containing compound (I) or a salt thereof and, as the first excipient, sugar or sugar alcohol； and (2) the second part containing pioglitazone or a salt thereof and, as the second excipient, sugar or sugar alcohol.
