Ostomy bag (10) includes that collecting bag (12) have the first side wall (16), interconnected peripherally with second sidewall (18), collecting bag (12) has the first and second side walls (16,18) between collecting chamber (20). Ostomy bag (10) further includes outlet device (14) connection and from collecting bag (12), outlet device (14) limits an internal channel (24) and is connected to collecting chamber (20), with closure member (26) in outlet (14), for selectively closing off outlet device (14). Outlet device (14) is formed separately collecting bag (12) and is connected to the outlet of collecting bag. Outlet device (14) and closure member (26), which can be formed together, is fixed on collecting bag (12) single processing step.
