The purpose of the invention is to create a urine bag that can be easily folded in order to occupy less space prior to use and that can be easily manipulated by a patient, in particular a paraplegic patient. This is achieved using a urine collection bag (1) formed by two sheets of plastic material that are stacked and welded along the periphery (2) thereof. The collection bag (1) comprises a collection compartment (3), an intake port (4) and an inlet (6) into the collection compartment (3), said inlet being in communication with the intake port (4) and delimiting the upper portion of the collection compartment (3). The intake port (4) is provided with a vertical extension (8) closed along their periphery (22) thereof and comprising a urinary catheter (9). The bag (1) of the invention is characterised in that the intake port (4) and the inlet (6) are offset vertically, and in that the vertical height (ho) of the bag (1) corresponds to a multiple of the height (hp) of the extension (8).
