In the current study, The variations exist in acceptance percentage of grafted larvae, emergence percentage and weight of virgin queens were investigated in queenless rearing colonies of local carniolan race (Apis mellifera carnica) with different worker populations in Manzala region as isolated area. The accepted percentage of grafted larvae in different worker populations was varying from 52.4 to 100.0% and the variations were significant by different between higher and lower worker population. The higher value of accepted percentage showed in May, 14,2016, while the lower value appeared in February,16,2016. The variation in the emerged percentage between lower and higher worker population was also significant. The emerged percentage of virgin queens varying from 84.1 to 100%. The mean weight of virgin queens was 159.63 and 160.58 mg. for lower and higher worker population, respectively with no significant difference between them. The minimum, maximum and mean temperatures had a significant and positive effect on the studied parameters when the rearing occurred in colonies with lower worker. It could be concluded that the preparing queen rearing colonies with worker populations equal 1.5 kilogram or more is very satisfactory in producing good queens.