The invention relates to the radar interference technology field, and concretely relates to a portable high-frequency ground wave radar radio frequency interference inhibition method. Two monopole crossed rings are adopted by a high frequency ground wave radar receiver to serve as reception antennas. After channel calibration, radio frequency interference takes place in monopole channels of the two monopole crossed rings and in two respective crossed ring channels. A spatial domain subspace projection method is adopted to realize interference inhibition: setting a threshold and determining whether each frame includes radio frequency interference; and for frame periods with radio frequency interference, obtaining a radio frequency interference sample through signals of long-distance elements only containing interference, extracting a sub-space of radio frequency interference through Eigen value decomposition, and for signals of near-distance elements containing radio frequency interference and sea state information, projecting the signals onto an orthogonal sub-space of the sub-space of radio frequency interference to inhibit interference. The method has a great inhibition effect for dense radio frequency interference, and ensures that arrival angle results of monopole crossed ring antennas, estimated by a MUSIC algorithm, are reliable after interference inhibition.