Abstract: A nostril filter system that includes a filter assembly including a foam rubber nose insert member including a tubular nasal passage portion and a dome shaped naris portion; a pliable plastic insert member including a tubular top portion and a dome shaped bottom portion; a cone-shaped, second stage filter element; and a disk-shaped, first stage filter element; the second and first stage filter elements being insertable into the pliable plastic insert member in that order prior to inserting the pliable plastic insert member into the foam rubber nose insert member; the foam rubber nose insert member being insertable into a nostril of a user such that the tubular nasal passage portion is inserted into the opening of the user's nasal passage and the dome shaped naris portion is positioned within the naris chamber of the user's nostril. The system can also include a nose shroud member and two identical nose insert member holding structures that are detachably connectable to the nose shroud member.