A valve device includes: a housing having a communication passage forming a part of a path from an inlet to an outlet; and a valve body disposed to be rotatable about a valve axis in the housing. The valve body has a peripheral wall portion facing a communication passage port at one end of the communication passage, and adjusts an opening area of the communication passage port according to its rotation position. The peripheral wall portion has a closure portion capable of fully closing the communication passage port, and openings arranged apart from each other in the circumferential direction. The plurality of openings include a large opening and one or more small openings smaller than the large opening. The centers of the small openings are axially offset.