The tectonic regime in the Zagros orogeny is affected by the convergence of the Arabian and Eurasian plates, which causes many earthquakes each year with a mostly reverse mechanism in this region . In-situ stress measurement in areas of valuable underground reserves is necessary for modern geophysical studies of hydrocarbon reservoir. In this study, dominant directionthe of tectonic stresses caused by tectonic behaviors under the influence of shell convergence in the southwest of Iran have been estimated by using the focal mechanism of occurred Instrumental earthquakes and have been analyzed by WinTensor software . For this purpose, the focal mechanism of systemic earthquakes that have occurred in the region has been used. The study area was divided into 8 sub-areas. And the data were analyzed in the software for all 8 regions and finally the whole area. The results of the analysis showed that the direction of maximum horizontal stress in 7 regions is NE-SW, which follows the pressure from the Arabian plate to the southwestern part of the Iranian plate, only in the 8th region; The northwest of Fars province is in the direction of NW-SE tension, the reason for which can be attributed to the dominance of local geotechnical factors over the owner's pressure from the Arabic plate.