To investigate the structural deformation and motion response of large flexible floating collars in waves, a model experiment were conducted in a towing tank for both regular and irregular wave conditions. The floating collar model was fixed horizontally using four cables, and the displacements of test points on the collar were captured using the Qualisys system. Additionally, the mooring forces were measured using a load cell, while the wave elevation near the model were recorded by wave gauges. The amplitude response operators of the floating collar's vertical and longitudinal motions were analyzed, and spectral analysis was conducted for the motion of the collar under irregular waves. Furthermore, the response of the mooring loads under both regular and irregular waves were explored. The research found that the wave heights on the downstream side of the model were significantly lower than those of the incident waves. The elastic deformation of the floating collar exhibited different modes at different frequencies. The mooring cable tension spectrum decreased with increasing incident wave frequency in the low-frequency range, and there was a second peak above the wave frequency. This study offers meaningful insights into the dynamic behavior and hydrodynamic response of large flexible floating collars under varying wave conditions.