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In order to determine the relationship between the distribution of Acer hyrcanum "Hyrcanian Maple" and environmental factors in northern slopes of Elburz mountains, eight forest regions were
studied from east of Gorgan to Asalem in the west of Anzali. In each region, related to variable conditions, Including: presence and number of trees, different elevations above sea level, and variation
of slopes, 59 plots were selected and in each plot, following features were recorded: Region name, height above the sea level, direction of slopes, physiognomy, age of the forest stand, land uses,
scientific names of all trees, shrubs and herbaceous plants and percentage of vegetation cover. In six areas, soil profiles were dug and their properties were recorded. Meteorological and geological data were taken from literature and related organizations. Data analysis has indicated that Acer hyrcanum
goes up where the height of mountains allows. In northern, northeastern and northwestern slopes, the distribution and quality of maple trees are better than other slopes. Type of parent materials affect the
texture of soil and A. hyrcanum prefers light and medium soil textures. PH is reduced with an increase in elevation and A. hyrcanum prefers weak and neutral acidity and its distribution can be better with
an increase in the amount of organic materials. Temperature is reduced from east to west and from low to heigh elevations. Precipitation increases from east to west and from low to heigh elevations and
then is reduced with an increase in height above 2000m. The climate in all the regions is mountainous cold humid and A. hyrcanum tolerates coldness and drought. Human activities in the regions affect the
distribution and regeneration of A. hyrcanum and other trees.