Abstract: A moisture trap is disclosed of the type, used in fluid suction equipment for dentistry in particular, which comprises a negative pressure intake (1) consisting of a venturi (2) that draws in fluid and delivers it into a vertical separation chamber (3) having an outlet (6) at bottom via which liquids are discharged, and an outlet (7) uppermost via which air is exhausted. A trap according to the invention has a separator device, located between the chamber fluid inlet (9) and the air outlet (7), embodied as a column of components arranged in such a way as to create a tortuous passage through the separation chamber (3) in which the direction of the stream of fluid is changed several times.