The present investigation was undertaken to study inheritance of fertility restoration gene(s) and to determine the nature and magnitude of gene effects through generation mean analysis. For inheritance studies of fertility restoration both visual scoring/scoring with Becket’s Scale-1 (1971) was undertaken to establish inheritance of fertility-restoration genes. The dominance nature of fertility restoration gene(s) in F1 was observed in both crosses whereas gene(s) for sterility exhibited recessive nature. The scoring results substantiated staining results . Fertility restoration was observed to be governed by dominant genes (monogenic) in nature. Genetic analysis was carried out in two crosses viz., 15C(A) x I-318(R) and I-401(A) x I-318(R) for all six generations in both crosses with P1, P2 and F1 having 30 plants each and F2 (300 plants), BC1 (180 plants) and BC2 (180 plants).Analysis of variance indicated significant differences among genotypes for almost all traits.Significant positive heterotic combinations for grain yield and yield related traits in present study suggested the possibility of production of successful commercial hybrids in Zea mays L. by using CMS sources.