Absolute fecundity (Fa) of burbot Lota lota lota females from Lake Haƒcza was 47.3 - 439.8 × 103, the relative fecundity based on eviscerated weight (Fwo) was 617.9 - 1572 × 103, and that based of total weight (Fw) was 44.8 - 1234.5 × 103. Regression equations were calculated, approximating the most significant relationships between fecundity and total body length of burbot (Fa = 0.0138 Sl2.5678, Fa = 0,0099 Tl2.8129) and weight (Fa = 0.6481 W1.0144). Mean gonadosomatic indexes (GSI) increased slightly with body length from 3.9 to 8.8% for females and from 3.7 to 20.6% for males.