A metamaterial Magneticinductive Lens (MIL) with negative permeability was designed to improve the Signal-to-Noise Ratio (SNR) for ultra-high field Magnetic Resonance Imaging (MRI). The proposed MIL, fabricated on a FR-4 substrate with a thickness of 0.6 mm, consists of a two-dimensional periodic array of 6×6 capacitor-loaded metallic rings. The equivalent magnetic surface plasmons effect would be achieved in the MIL when it is placed between the RF coil and sample. In terms of the electromagnetic field distribution, the scattering parameters and the equivalent permeability, simulated results reveal that the evanescent harmonics could be heightened. In addition, the evanescent harmonics was excited by the RF coils at the Larmor frequency 297.2 MHz. By loading the MIL, the SNR of MRI images is enhanced about 200% in the sagittal images with a small water phantom, and approximately 58% in the coronal images with a large water phantom. Both simulations and MRI experiments clearly demonstrate that the magnetic field of RF coils could be focused by the metamaterial MIL, which is beneficial to improve the SNR, spatial resolution and detecting depth of MRI.