Wave run-up on deepwater offshore structures may contribute to wave overtopping of the platform deck. It may also cause undesirable loads including impact loads on the underside of the deck when combined with other hydrodynamic phenomena beneath the platform deck. In this study a 1:40 scale model of an unmanned mini-TLP design was subjected to a series of design sea environments for the Gulf of Mexico. Complimentary testing of compliant and fixed hull configurations was performed and the wave run-up was measured at several locations around the hull in both head and quartering sea orientations of the platform. The wave elevation data reported here was obtained at three critical points on the hull and a reference wave gage well upstream of the model. Analysis of the data was performed using an orthogonal third order Volterra series system analysis technique. The wave run-up measurements were compared and correlated to the incident wave elevation measurements. The results indicate that the run-up is more pronounced in the rigid hull model configuration than for the compliant model configuration and this was the case for both headings. Further, the analysis revealed a strong linear relationship between wave run-up and the incident wave field over the high wave energy frequency band. This result adds credence to the previously proposed simplified computational procedures for estimating the second order wave run-up on large cylinders in random waves.