The performance of an animal for a particular trait is the result of its genetic merit and the effects of the environment where it exists. To set up genetic improvement in sheep, the genetic component attributed to the trait of interest need to be defined. The aim of this review was to describe major candidate genes influencing growth traits and prolificacy in sheep. Although growth and prolificacy are quantitative traits and are expected to be influenced by many genes with individual genes contributing small effects, there are major genes that have been identified with significant influence on growth and prolificacy. The CLPG, GDF8 and CAST genes are some of the major genes that have strong influence on sheep growth and carcass quality. The CLPG mutation can cause pronounced effect in the muscle found in the hindquarter and is responsible for the muscular hypertrophy phenotype in sheep. The GDF8 gene also play important role in increasing muscle depth due to mutation in the regulatory region and coding sequences. The CAST gene is an endogenous and specific inhibitor of calpain enzyme and thereby regulates the rate and extent of muscle tenderization following slaughtering. For prolificacy, BMP15, GDF9 and BMPR1B have been shown to exert significant influence on ovulation rate and litter size in various sheep breeds in the world. Both of the three genes are member of the TGF-beta family protein that encode protein product responsible for growth, differentiation and proliferation of ovarian follicles. The mechanism of action for such major genes are associated with the existence of mutation in the coding sequence resulting amino acid change as well as in the regulatory region that vary the expression level and inheritance of the genes. Up to now, better attempts have been made to describe the genetic basis of growth and prolificacy in sheep. However, more works are needed to characterize other genes influencing these traits. More importantly, making use of the identified genes in sheep breeding program through marker assisted and genomic selection should receive due attentions.