An adjustable respiratory mask includes a nasal cover (1) and a forehead fixing base (2). The nasal cover (1) includes a frame assembly (11) and a cover body (12). The frame assembly (11) has an upright frame (111) and an adjustable support (112) extending from the upright frame (111). The upright frame (111) is connected to the cover body (12). The adjustable support (112) is a plastic piece and inclined relative to the upright frame (111). The forehead fixing base (2) has a base body (21) provided with a receiving portion (213). The adjustable support (112) penetrates the receiving portion (213) to allow the base body (21) to adjustably move. Thus, the respiratory mask of the present invention can fit face contours of different users, so that the users can feel more stable and comfortable when wearing it.
