Cyclones are monolithic and instable systems in which the air pressure is low, the air flow is ascending and the wind direction in the northern hemisphere is counter clockwise. Due to vertical movement of the air in cyclones, the possibility of the appearance of clouds, precipitation and even a thunderstorm is provided. In this research, in order to recognize the cyclones and to study the spatial situation of the influencing cyclones on Iran during 1991, the evaluated data of geopotential height of NCEP/NCAR related to the National Oceanic and Oceanographic Authority of the United States with a 6-hour time zone and spatial separation of 2/5*2/5 degrees in 6 height levels of 1000, 925, 850, 700, 600, 500 hectors Pascal. The data has been taken for the range between the -30 western to 80 eastern longitudes and the 0 to 80 northern latitudes. The results show that the highest and the lowest cyclone frequencies are related to the levels of 500 and 700 hectors Pascal and also in the 6 studied levels (500, 1000, 925, 850, 700 and 600 hectors Pascal), winter and fall have the highest cyclones, while with a little difference, spring and summer have the lowest cyclones. The spot analysis of the recognized cyclones represented that Gang cyclone is the main cyclonic occurrence in the maps of 1000 level in spring and summer but in higher levels and in the fall, they would disappear and in the Mediterranean Sea at the level of 1000 hectors Pascal and in spring and summer, no cyclonic centers are observed but gradually in higher levels, the frequency is increased such that it reaches the highest amount in the level of 500 hectors Pascal in the winter. The cyclone of north Atlas is approximately present in all the studied cyclones during the year.