We have fabricated a novel InP-based multimode interferometer combined with a metamaterial. It consists of an array of extremely small metal split-ring resonators attached to the waveguide. In this manner, we have demonstrated magnetic interactions between the metamaterial and light traveling in the device, the device was designed for use at 1.55 μm wavelength. The transmission characteristics of the device strongly depend on the polarization and wavelength of the input light. Our results show a strong possibility of creating novel semiconductor devices, i.e., meta-photonic integrated circuits.