In this thesis, the noise levels on board self-propelled dredging vessel caused by ship engines and devices, have been assessed by the hybrid Statistical Energy Analysis (SEA). After the introduction, definition of basic terms in technical acoustics are provided with particular emphasis to main noise sources and noise propagation ways on board ships. Furthermore, actual rules and regulations related to noise problems in ships have been dealt with, and overview of basic numerical methods for noise assessment has been provided, where special attention is paid to hybrid SEA, due to its application in the illustrative numerical example. Ship particulars and main noise sources are listed together with noise excitation levels. A commercial software package Designer-NOISE, available at the Chair of Marine Engineering of the Faculty of Mechanical Engineering and Naval Architecture is used for the noise level assessment on board the vessel, whereas model generation and noise analysis procedures, respectively, have been described in detail. The results include noise levels for a range of ship compartments for two typical operating modes, i.e. sailing and dredging. For those compartments where excessive noise levels are obtained, appropriate technical solutions have been recommended in order to decrease them to the acceptable values. Finally, together with the concluding remarks of this thesis, challenges in ship acoustics have been discussed and some guidelines for further investigations are drawn.