The Earth's gravity field is related to the Earth's mass and shape and to the position, where we apply the measurement.The measured value in any place depends on the altitude of the place angle and Earth's rotation speed around itself. In the paper we present a theoretical idea connecting the value of gravity with the above mentioned amounts. Next we calculated the value of this field in some Syrian cities. The paper is ended by important note, that the obtained relations allowing to calculate the value of the gravity field depends on the place altitude, not on the one's Longitude.