Seismic values are the main parameters in evaluating the neotectonic activity of a region. The b-parameter as the slope of a magnitude-frequency diagram is related to the tectonic characteristic of a region and its variations could indicate the heterogeneity in this region. In order to evaluate the neotectonic activities and seismic pattern of the Hajdak area, the spatial variations of b-parameter were used as one of the seismic parameters before the earthquakes of 10 and 12 December 2017 with Mn= 6.2. The map of the spatial distribution of the magnitude-frequency is drawn up showing a specific variation of 0.5 to 1.5 for b-parameter. The results of the calculations show that b-parameter has a significant reduction in relation to the earthquakes occurred in a region with a high stress rate.