In this study the distribution and infection percentage of infected trees toLoranthus europaeus in various height above sea level classes areas were investigated. For this purpose 65 circular sample plots with an area of 500 m2 were taken in Mirabad forests of Sardasht. Quantitative characteristics like DBH, tree height, crown height and diameter were measured in each plot. Results showed that the highest percentage of infected trees in all three Oak species (Quercus brantii, Q. libani and Q.
infectoria) were on the highest elevation class (1751-1800 m) and the lowest percentage of infected trees were on lowest elevation classes (1450-1550 m). Percentage of infected trees in highest elevation class was about 4 to 3 times more than percentage of infected trees in lowest elevation classes. Mean number ofL. europaeus per tree in Quercus brantii and Q. infectoria in highest elevation class was almost 2 times more than lowest classes (elevation range from 1551 to 1600 m) and forQ. libani it was 3 to 5 times more than lowest classes (1450 -1550 m). Eventually, for effective fighting with this pest, it is better to start from upper altitude.