Hybrid propulsion system for a pleasure boat and provided with a control system of the hybrid propulsion system and of the position of the pleasure boat, the hybrid propulsion system further comprising an internal combustion engine and an electric motor/generator (30, 31, 32) operating in an integrated manner and according to two operating modes managed by the control system: - a first operating mode in which the internal combustion engine is configured to operate at cruising speed, and - a second operating mode in which the electric motor/generator is configured to operate at a lower speed than a cruising speed, in which: - the control system comprises a plurality of gyroscopic sensors and/or triaxial accelerometers (20, 21) and is configured to control the position of the boat by means of signals from said plurality of gyroscopic sensors and/or triaxial accelerometers (20, 21), and - the plurality of gyroscopic sensors and/or triaxial accelerometers is located such that there is at least one gyroscopic sensor and/or one triaxial accelerometer at the bow of the boat and at least one gyroscopic sensor and/or one triaxial accelerometer at the stern of the boat, the hybrid propulsion system being characterised by the fact that the control system comprises - at least one logic block (41, 42) and at least one feedback block (43, 44), the at least one logic block (41, 42) being configured to compare set-point signals (W1, W2) with feedback signals from the at least one feedback block (43, 44), - at least one regulator (45, 46) configured to determine the value of a regulating variable (Uyl, Uy2) on the basis of the value of a variable to be regulated, and - a control unit configured to transform the values of the regulating variable (Uyl, Uy2) into input values (Yx1, Yx2 and Yz1, Yz2) for said electric motor/generator (30, 31, 32) of the hybrid propulsion, and wherein - the set-point signals (W1, W2) are static or dynamic angular values, - the feedback signals are angular values from the at least two gyroscopic sensors and / or triaxial accelerometers (20, 21) at the bow and at the stern that provide data on the variations of the x and z components of the displacement vector, - the regulating variable (Uyl, Uy2) is a driving torque, and - the input values (Yx1, Yx2 and Yz1, Yz2) are a propulsive thrust according to two directions defined by x and z components of the displacement vector. - a first operating mode in which the internal combustion engine is configured to operate at cruising speed, and - a second operating mode in which the electric motor/generator is configured to operate at a lower speed than a cruising speed, - the control system comprises a plurality of gyroscopic sensors and/or triaxial accelerometers (20, 21) and is configured to control the position of the boat by means of signals from said plurality of gyroscopic sensors and/or triaxial accelerometers (20, 21), and - the plurality of gyroscopic sensors and/or triaxial accelerometers is located such that there is at least one gyroscopic sensor and/or one triaxial accelerometer at the bow of the boat and at least one gyroscopic sensor and/or one triaxial accelerometer at the stern of the boat, the hybrid propulsion system being characterised by the fact that the control system comprises - at least one logic block (41, 42) and at least one feedback block (43, 44), the at least one logic block (41, 42) being configured to compare set-point signals (W1, W2) with feedback signals from the at least one feedback block (43, 44), - at least one regulator (45, 46) configured to determine the value of a regulating variable (Uyl, Uy2) on the basis of the value of a variable to be regulated, and - a control unit configured to transform the values of the regulating variable (Uyl, Uy2) into input values (Yx1, Yx2 and Yz1, Yz2) for said electric motor/generator (30, 31, 32) of the hybrid propulsion, and wherein - the set-point signals (W1, W2) are static or dynamic angular values, - the feedback signals are angular values from the at least two gyroscopic sensors and / or triaxial accelerometers (20, 21) at the bow and at the stern that provide data on the variations of the x and z components of the displacement vector, - the regulating variable (Uyl, Uy2) is a driving torque, and - the input values (Yx1, Yx2 and Yz1, Yz2) are a propulsive thrust according to two directions defined by x and z components of the displacement vector.