Some biological characteristics of 10 local and internationally well-known plum cultivars grown in Gornje Polimlje, Montenegro were studied between 2009-2011. Cacanska Rodna, Cacanska Lepotica, Stanley, Cacanska Rana, Valjevka and Valerija cultivars showed high productivity. The highest fruit mass was obtained from California Blue cultivar while the smallest fruit mass was measured for Pozegaca cultivar in all measured years. Soluble Solid Content (SSC), total acidity, total sugars, reducing sugars, sucrose, cellulose, vitamin C, total anthocyanin and ash content of plum cultivars were between 12.60-20.40%, 0.66-1.15%, 10.65-15.24%, 7.17-11.94%, 1.16-6.07%, 0.30-12.49%, 10.69-15.50 mg.100 g(-1), 0.6-7.7 mg.100 g(-1) and 0.55-0.78%, respectively. The amount of potassium, which predominates in percentage of minerals in the ash, ranged from 1893 to 2199 mg.kg(-1). Local cultivar Pozegaca had the highest content of potassium, magnesium, calcium, iron, soluble solid content and vitamin C, and second highest content of iron, sugar, reducing sugars and cellulose. Anna Spath had the highest content of iron and sucrose. Highest content of sugar and anthocyanin was observed in Stanley cultivar. Total acids and reducing sugars were highest in cultivar Cacanska Lepotica.