Abstract: The machine (1) for producing porous membranes (2) for medical use comprises a plurality of reserves (25a, 25b, 25c, 26a, 26b, 26c) of components (18a, 18b, 18c, 19a, 19b, 19c) which constitute fluid substances, first and second guns (16, 17) supplied from the reserves (25a, 25b, 25c, 26a, 26b, 26c) for spraying the fluid substances onto an element (37) on which the substances are deposited and build up, the element (37) and the guns (16, 17) being mobile relative to one another for substantially even distribution of the fluid substances designed to form the membrane (2).