Spatial patterns are suitable tools for optimal management in many forested areas. In this research، the effect of conservation on spatial pattern of dominant trees has been studied. To achieving this purpose، protected and non- protected forests were selected in Masal region of Guilan province as the study area. Sampling methods including fixed- area plots and distance methods، such as T- square and compound sampling were used 25 circle sample plots، each with an area 1000 m2and 25 sampling points were taken. Then، tree species in plot samples and the distance of interest were identified and measured. Dispersion indices such as Green، Morisata، standardized Morisata، Hopkins، Eberhart، Johnson and Zimmer، Hines and C were used to analyze the spatial pattern in the areas. All indices related to plot samples indicated the clumped pattern for dominant species in protected and non- protected areas. The results of the distance indices have indicated that destruction changes the spatial pattern of dominant species and these species had different pattern in these areas. Among the distance indices، C and Hines indices revealed differences and they were suitable to describe the spatial pattern of both areas.