A cabin for wellbeing treatments using steam, comprising steam feeding means (5) and at least one steam diffuser (6) located in an inner compartment (4) of the cabin and fed by the steam feeding means (5), the diffuser (6) comprising a containment body (8) which is open at least at the top, an upper closing element (15) substantially mounted at an upper part of the containment body (8) in such a way that between them at least one slit (16) is formed which puts in communication the inside of the containment body (8) and the surrounding environment, and at least one steam dispenser (17) which is fed by the steam feeding means (5) and located inside the containment body (8) below the closing element (15). A steam dispensing device comprising the feeding means (5) and the diffuser (6) is also claimed.
