Abstract: The damage of bark beetles in Uludag Fir (Abies nordmanniana subsp. bornmulleriana Mattf.) stands at Ilgaz Mountain, Cankiri and the relationships between height-diameter at breast height (DBH), crown diameter-DBH and crown diameter-height were also investigated in this study. Bark samples obtained from Uludag firs at various ages and dbh from study area which were pure Uludag fir stands, were brought to laboratory and determined bark beetles were identified. It was determined that the most common and harmful bark beetles were Cryphalus piceae (Ratz.) and Ips (Pikyokteines) curvidens (Germ.) in Uludag fir dominated stands of 50-100 age and 15-40 cm dbh. It is necessary that yearly outbreak area and intensity surveys should be conducted in order to minimize bark beetle damage. Five sample plots were selected from pure Uludag fir stands in study area and certain properties were measured on the living trees. After the regression analysis carried out, it was determined that there were statistically significant (p<0.001) and strong (R2>0.50) relationships between DBH, height and crown diameter variables in Uludag firs. The strongest relationship determined was the crown diameter-height relationship (R2 = 0.959), followed by the tree height-DBH (R2 = 0.844) and crown diameter-DBH (R2 = 0.805) relationships, respectively.