A swimming pool cleaning apparatus (10) may include a body (11), a hydraulic circuit for liquid circulation between a liquid inlet (13) and a liquid outlet (14) and through a filtration chamber (17), driving and guiding members (12) of the body on a submerged surface, and defining a guide plane (XY), and an adjustment mechanism (30) for the orientation of a liquid flow, disposed at the outlet of the liquid outlet. The adjustment mechanism is adapted to direct the flow of liquid that escapes from the liquid outlet in (at least) two predefined directions, one of which (33) corresponds to a first direction inclined with respect to the guide plane and the other of which (32) corresponds to a direction substantially perpendicular to the guide plane.