An air distribution apparatus (1) for agricultural sprayer machines (A), comprising a tubular casing (2) which mainly develops along a first longitudinal direction (Y) and has a plurality of through holes (3) which allow the communication between the inner volume (4) of the tubular casing (2) and the outer environment and consequently the treatment, by means of pesticides supplied in spray form, of plantations, orchards or cultures arranged in trees and/or shrubs rows, is delimited and closed, in its upper part (2a), by a first cover (5) and, in its lower part (2b), by a second cover (6), and is provided in the upper part (2a) with a shaped plug (7) suitable to receive the application of a connecting sleeve able for conveying the air coming from a production and displacement device of the air itself, into the tubular casing (2). In particular, the air distribution apparatus (1) comprises, at each of the through holes (3) of the tubular casing (2), deflector means (8) firmly coupled with the inner wall (2c) of
