Abstract: A shut-off device for low-temperature media includes a housing (2), a valve seat (5) located in the housing (2), and a valve (3) that cooperates with the valve seat and is pivotally supported in the housing (2). On the housing (2) there is at least one flange (10) for mounting the shut-off device in a pipeline. The low-temperature shut-off device, low construction cost and low maintenance cost is achieved because the flange (10) of the housing (2) is designed as a welding flange (10a, 10b) for attachment of the shut-off device (1) in the pipeline by a weld joint, especially a butt weld joint, and because the housing (2) is provided with a housing opening (11) for mounting and/or removing the valve (3).