Abstract: An experiment lasting almost 10 years was conducted to investigate the effects of crossing 6 Finnish landrace rams with 60 Awassi ewes on prolificacy and other traits using (A.I.) first generation was produced (50% Finnawassi). Blood samples were taken for haemoglobin typing. Finnawassi ewes were back crossed to produce 75% Finn and 25% Finnawassi. A comparison was done between different Finncrosses on suitable crossbred generation in sustaining sub-tropical conditions and heat-tolerance; prolificacy, growth and conformation. Twining % in local Awassi was increased from 5 to 35% within 9 generations (+30%). Crosses of 50 and 25% Finnawassi were found more suitable for local sub-tropical prevailing conditions than 75% Finncross. These were lower tolerance to hot and harsh conditions, suffer higher mortality and less hardiness than other crosses. Although 1st generation lambs had significantly lighter weaning weights (P<0.05) than local Awassi (20.4 vs 24.3 kg). However, Finnawassi had much better growth rates than Awassi (264 vs 221 gm perday). Tail length in Finnawassi was reduced significantly by >26% (20.9 vs 15.4 cm) and tail width was also reduced significantly by >48%. It is concluded that it is worth crossing local Awassi with prolific (i.e Finnsheep) breeds to improve prolificacy, growth rate and reduce tail size in 50 and 25% Finncrosses under well managed farms.