An inlet device (17) for a gravity separator (18) for separating a fluid mixture including gas and liquid. The inlet device (17) includes an inlet nozzle (1) for the fluid mixture, a distribution chamber (2) connected to the inlet nozzle for distributing the fluid mixture to one or more axial cyclones (3) constituting an integral part of the inlet device (17) and being connected to the distribution chamber (2). The axial cyclones (3) are provided with a bottom inlet opening, a top outlet opening (9) for the gas rich fluid stream, a swirl inducing element (21), one or more openings (24) to allow liquid to leave the axial cyclones (3), and to be drained to a level below the inlet device (17).