The present invention relates to a hybrid-type watercraft propulsion system (10) having an engine (14) and an electric motor (16) as a source of driving force for a propeller (12) and comprising a setting means such as a controller (42) configured to set a propeller driving mode according to instructions input via a single instruction means such as a control lever (46), said single instruction means (46) being adapted for mutual input of instructions regarding the operating mode of the system (10) as well as an amount of output power of the driving source (14,16).