An exposure apparatus for exposing a substrate by emitting exposure light thereto through a projection optical system and liquid, has a detection apparatus that detects whether the liquid is present on an object disposed lower than a front end of the projection optical system. Another detection apparatus has an emitting portion that emits detection light to an immersion area between the projection optical system and an object disposed on an image plane side thereof, and a light-receiving portion disposed at a predetermined position for the detection light; therein, at least one of size and shape of the immersion area is obtained based on light receiving results. The detection apparatus is used to detect the presence of liquid on such lower-disposed object, the state of the immersion area, or shape or contact angle of the liquid. Optimal measures are taken, based on detection results, for maintaining high exposure and measurement accuracies.