In order to establish the effect of genealogical line of herd rams on the quantity and quality traits of wool and live weight was conducted a study on two groups of rams at 1.5 years of age of the Karnobat fine wool breed. The animals of the first group (153 in number) were born in the period 1991-1996 year, and the second group (63 in number) were born in the period 2002-2007 year. The rams had a comparative assessment by own productivity, and the animals were from 4 genealogical lines. Line 2081 and line 777 originated from breeding Australian merino, and line 1825 and line 576 – from rams of the North-EastBulgarian fine wool breed.The data on wool productivity, wool yield, clean wool, staple length, wool thickness and live weight was processed by the methods of variation statistics and were adjusted by the year impact. Between the lines of the Karnobat fine wool breed was established certain differentiation, as by the trait of wool productivity was distinguished line 777, by wool yield, clean wool, staple length and live weight – line 2081, and by wool thickness – line 576. During the period of 1991-2007 year the wool productivity, amount of clean wool and live weight were slightly lower, whereas the wool yield was significantly increased. Wool thickness was preserved within the requirements for merino wool