In order to investigate the effective protection methods against offshore wind power monopile foundation scour, three composite protection methods, namely riprap with flexible curtain, biomimetic aquatic grass with riprap and horizontal baffle with sleeve, are proposed to protect against scour under wave action in a specific engineering project. The physical model tests are carried out in a wave flume to analyze the scour morphology and maximal scour depth around the pile foundation under different protection methods. The results show that: the flexible curtain can reduce the shear effect of the submerging currents and horseshoe vortices on the seabed and reduce the loss of sediment; the biomimetic aquatic grass can provide similar effects while also reducing the forward flow velocity and preventing secondary scouring; the sleeve can compensate for the vulnerability of the edges of horizontal baffle to scouring when used alone. All three protection methods show good performance in mitigating scour under wave conditions, with the combined protection of horizontal baffle and sleeve being the most effective.