A ship propulsion (3) with at least a fixedly positioned transmission unit (4, 204) secured to the hull (6) of the ship and a propulsion unit (5, 205) located on the exterior of the hull. The ship propulsion (3) facilitates pivoting of the propulsion unit (5, 205) around a control axis (10, 110, 210, 310), via a control device (200, 300). The control device has a control motor (120, 220, 320) and at least one control transmission (130, 230, 330). The control transmission is designed as a reduced planetary transmission, which comprises two central gears (131, 132, 231, 232, 331, 332) and a planetary gear carrier (233, 333, 433) with at least two planetary gears (238, 338), and coaxial positioned with reference to the control axis.