Computational and physical modelling of the Sea Organ was carried out with purpose of analysing the existing functionality of the entire system. This thesis describes the location and the wind-wave climate in front of the Zadar coastline, as well as the structural, hydraulic and acoustical characteristics of the Sea Organ. The computational model for simulating the Sea Organ was also described and presented in detail. The model consists of three integral parts: the sea surface model, the model for water mass oscillations in pipes, and the sound model. Based on the collected and thoroughly studied data on the Organ functionality, a physical model was constructed with a purpose of validating the computational model. The experimental analysis was carried out in the Hydraulic laboratory at the Faculty of Civil Engineering in Rijeka, and all the technical equipment details and analysed scenarios are described in the thesis. In the last chapter, several experimental results are presented by illustrating the agreement between the results obtained by the computational and physical model. Also, parametric analysis of the influence of different pipe dimensions on the Sea Organ functionality was carried out. In addition, the influence of wave dynamics on water level oscillations in pipes are also shown, and so is the final sound. Based on the analyses that were carried out, the main conclusions were stated about the Sea Organ functionality and the possibilities of using the computational model as tool in the design phases of similar structures.