The present invention discloses a MIMO antenna system, which comprises a first radiation unit layer, a second dielectric slab unit layer and a third ground unit layer. The first radiation unit layer is printed on the front side of the second dielectric slab unit layer; the third ground unit layer is printed on the back side of the second dielectric slab unit layer; and the first radiation unit layer comprises a main antenna radiator and a parasitic element. By using the invention, the mutual coupling between the antennae of the MIMO system can be reduced, thereby the isolation of the MIMO antenna system. is improved. The invention can be widely used in the technical field of antennae.