Abstract: A washing unit for machines that clean ophthalmic glass (1) or other substrates, it includes, on one hand, two washing lines (22, 23), each able to issue a high-pressure jet of washing liquid in a flared shape of a width substantially equal to or greater than the diameter of the glass to be cleaned, said lines (22, 23) being parallel and mounted opposite each other on each side of the glass (1) to be cleaned so that the two streams of liquid (30) are located at the same level and come into contact on the concave (10) and convex (11) surfaces respectively of said glass (1); and, on the other hand, supports (4) intended to hold the glass (1) in a stable position during the washing operation and the means (2?) to allow movement of said lines (22, 23) or the glass (1) in order to perform simultaneous bathing of the concave (10) and convex (11) surfaces of the glass by the respective strains of washing liquid (30).