In this paper, according to three kinds of seismic patterns as precursory of strong earthquakes, i. e. aftershock burst pattern b, earthquake swarm patterns and weight sum pattern ∑, put forward by Keilis-borok and Knopoff et al., taking Kangding-Luhuo seismic zone as a example, the existence and prediction effect of three kinds of seismic patterns are tested. The results show that, during 1967-1982, one, two and all of three kinds of seismic patterns can be produced in the seismic zone before 5 strong earthquakes (M≥6.0). The prediction effect of three kinds of patterns are rather satisfactory. Particularly, the prediction effect of the weight sum pattern ∑ is better. When the value of the pattern ∑ exceeds certain threshold value, there always were earthquakes (M≥0.6) to occur afterwards. Simultaneous appearance of two or three kinds of patterns can eliminate false forecast and improve the accuracy of earthquake prediction.