Three typical asymmetric waves were generated repeatedly for the measurement and estimation of forces of a TLP. A model for prediction of the forces on columns and pontoons was employed to predict the wave moment of component structure. The resultant forces and moment time series are used to simulate the nonlinear response motions and tether tensions. The tension spectrums around the resonance frequencies are filtered to observe the tension behaviors. Strong and weak asymmetric waves respectively produced impact and nonimpact on the platform and ringing and springing in tendons.