The invention provides a method for detecting nucleic acid point mutation. Specially, the method of the invention comprises: a nucleic acid sample to be detected is hybridized with the probe of the invention so as to detect whether a nucleic acid to be detected-probe hybridization compound is formed or not; an artificial mismatching locus is additionally introduced into the probe sequence of the invention so as to generate two mismatching locus between a probe binding area and a point mutation containing sequence to be detected. When being used, the probe of the invention has obvious difference on wild and mutant detection signals by the probe in the reverse hybrid detecting nucleic acid point mutation so as to definitely judge the detection result. Experiments show that the invention can effectively improve the detection signal-to-noise ratio so as to improve detection sensitivity.