Aim of the current study was to evaluate the effect of nigella sativa oil (NSO) supplementation under hot and mild Egyptian conditions, on physiological thermoregulatory response, blood components, gestation length, feed and water consumption during gestation and suckling period, litter size and weight at each of birth, 21 d and 30 d (weaning) of age and mortality rate of pups from birth to 30 days of age. Thirty New Zealand White (NZW) adult doe rabbits (15 in hot season and 15 in mild season) aged 6 months and weighed 2935.4 g were used. Results showed that feed intake, water consumption, rectal temperature, respiration rate, litter size and weight at birth, 21 d, weaning, pre-weaning mortality rate were affected significantly (P<0.01), while the gestation  period, serum total proteins , albumin, globulin, urea and creatinine were not affected significantly by season. Supplementation the doe rabbits diet with NSO (30 g oil / kg diet) significantly improved litter size and weight at birth (P<0.01 and P<0.05), at 21 d and at weaning (P<0.05), while pre-weaning mortality rate, gestation period, feed intake, water intake, rectal temperature, respiration rate, serum total protein, albumin, globulin, urea and creatinine concentrations in blood plasma of does were not affected.It could be concluded that, feeding doe rabbits during the hot season with dietary supplementation of 30 g Nigella sativa oil/kg diet is very effective on productive and reproductive performances of rabbits.