In a method for navigating an undersea vehicle (12), navigation data about position, orientation, and absolute vehicle speed of the undersea vehicle (12) are determined from measurement data delivered by navigation sensors (17) via a navigation filter (18) which incorporates the measurement values of a Doppler log (14). To achieve a highly accurate tracking of the course taken by the undersea vehicle (12), particularly during submerging and surfacing phases, the stretch of water (10) traversed by the undersea vehicle (12) is divided into regions (13) which at least in the vertically oriented z-axis have a finite dimension within a Cartesian coordinate system (11). During the voyage of the undersea vehicle (12), the flow rates in the stretch of water (10) in relation to the individual spatial layers (13) are determined and stored from the relative vehicle speeds measured by the Doppler log (14) in successive measurement processes, and from the absolute vehicle speeds issued continuously by the navigation filter (18). The stored flow rates are input into the navigation filter (18) (FIG. 1) in accordance with the respective spatial layer (13) reached by the undersea vehicle (12).