This investigation !Jas carned out under fie ld condi. tio n to study the nature of resistance for 20 Ft' B cross and their 5 parents to common smut disease in maiBe.. Genetic analysis suggested that the additive genetic variance played a major role in the ezpression of this trait. The Largest part of the total genetic variabi1.ity uae due to additive and (additive X additive) gene action. There !Jere significant differences for general and specific combining ability for resistance. but the amount of general combining abi"Zity !Jas higher than the amount of specific combining abi"Zity. Single crOBS 104 and S.C. 105 !Jere good general combiners for the resistance. !Jhi1.e S.C. 9. S.C. 10 and S.C. 103 !Jere poor general combiners. The double crosses (13:5). (33:2). (43:3). (33:5). (53:3) and (43:5) !Jere superior for resistance. Nature of resistance !Jas assessed by measuring the content of phenolic compounds in inoculated and non-inoculated plants. Total. free and conjugated pheno ls !Jere determi ned in the parents and their 20 FI' e; P1.ants !Jere high contents of phenolic compounds sho!Jed high resistance to the disease.