A Five-year crossbreeding project involving Spanish maternal line called V-line (V) and Saudi Gabali (S) rabbits was carried out to produce new maternal and paternal lines to be used as parents in Saudi Arabia particularly in El-Qassim region. Ten genetic groups were produced through six generations. An animal model was used to estimate breeding values for economic traits to be used for selection across generations. In practice, synthetic lines of rabbits naming Saudi 2 (as a maternal line) and Saudi 3 (as a paternal line) were being formed in this project successfully to be convenient in Saudi Arabia and other hot climatic areas. The synthetic maternal line (Saudi 2) could be used in commercial scale as a pure line or to be crossed with other maternal males to get crossbred does, while the paternal line (Saudi 3) will be specialised in high rates of growth since the program is still currently running to attain more complete benefits of such project to synthesize new lines. These synthetic lines are characterized by high lactation associated with rich total solids in milk and heavier litter weight at weaning associated with lower feed conversion ratios of feed to milk and milk to litter gain and high carcass and meat qualities.