Multipath interference is a main factor of having influence on detection in super-low altitude. Antimultipath methods under condition of diverse battlefield environments are studied. By the hybrid method PO+MEC of Physical Optics (PO) and Method of Equivalent Currents (MEC), this paper calculates the electromagnetic scattering characteristic of missile target. Antenna radiation pattern of seeker is introduced to modify traditional Four Path Method (FPM). The multipath interference of super-low altitude missile target under diverse battlefield is extracted. The simulation results show that the different battlefield has corresponding Brewster angle. The Brewster angles of concrete, dry land, half-dry land and wet land environment are 30°, 26.5°, 21.5°and 10.5°respectively. When seeker of air-defense missile takes the VV polarization mode with the Brewster angle to detect super-low altitude missile target, multipath interference reaches minimum level, and the signal to interference radio reaches maximum level. At this moment, the seeker has the best detection capability to super-low altitude missile target and the target echo is the most obvious.