Through analysising the seismicity data before M_L ≥ 5.0 earthquakes in Ningxia and its adjacent areas since 1965, it is found that there mostly is the characteristics of enhancement of moderate earthquakes before M_L ≥ 5.0 earthquakes. In A part of the study area, the probability for occurrence of M_L ≥ 5.0 earthquake is 0.71 after anomaly of the enhancement of moderate earthquakes in 7 months; and it is 0.60 in 3 years in B part. The probability that earthquake locats near the outer linked lines of all earthquakes in one enhancement of moderate earthquakes is 0.79. Its R -value is 0.75. So the enhancement of moderate earthquakes can be a middle period prediction method for M ≥ 5 earthquake in this region.