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Coulomb stress variations may trigger earthquakes, while the stress transfer process is not clear. In this paper, Coulomb stress changes are investigated for the sequences of strong earthquakes in the Caucasus region, which followed the 1988 M w 6.8 in Spitak, the 1991 M w 6.9 in Racha and the 2000 M w 6.2 in Baku. Our results show that the mainshocks induced variations in the stress field where most of the seismic events occurred. Coulomb stress increases 2 bars corresponding nearly to places of aftershocks, while the stress falls above 10 bars for Racha mainshock. The calculated Coulomb stress loaded about 5 bars at the end of rupture plane and the stress falls ~9 bars for Spitak mainshock. Our stress pattern shows a correlation within the areas of Coulomb stress caused by the combination of seismicity. Correlations between the coseismic Coulomb stress changes and the observed spatial patterns of the aftershocks created by the mainshock are illustrated by the stress variations over both optimally oriented and specified fault planes. An apparent correlation between the mainshock stress changes and the detected spatial pattern of the aftershocks is found, confirming the utility of the stress maps in constraining the expected locations of the forthcoming aftershocks and mitigating earthquake hazards. • Coulomb stress changes are calculated on M w ≥ 6 earthquakes in the Caucasus. • The regional stress orientations and Coulomb stress are estimated on optimally oriented planes. • The seismicity rate differences are correlated with the estimated Coulomb stress changes. • Stress changes make a significant difference in the region with relatively high seismicity rate. [ABSTRACT FROM AUTHOR]