An exposure apparatus transfers a pattern of a mask onto a substrate and includes a covering member which is disposed in the exposure apparatus and which substantially isolates a predetermined spacing from outside gas. The covering member includes a first thin film made of a first material which blocks penetration of the outside gas with respect to the predetermined spacing and a second thin film having a low degasification property and made of a second material of at least one of a metal and an inorganic substance. An exposure method transfers a pattern of a mask onto a substrate and includes the steps of isolating a part spacing of an optical path spacing for an exposure beam which transfers the pattern of the mask onto the substrate from outside gas by using such a covering member.