Abstract. The general combining ability (GCA) and specific combining ability (SCA) of twenty-six middle early maize lines was studied by Savchenko’ method. The lines were tested on three testers, with origin of two genetic groups: ХМ 98 40 and КС 05 7 of SSS и ХМ 87 15 of Lancaster. Highest GCA have lines КС 08 12, КС 08 10 and XM 08 8. These lines will be included as components of high-yielding middle early synthetics or as testers in analyzing crosses to determine of GCA in early stages of the selection process. With high SCA are the lines KC 08 29, XM 08 4 and XM 08 10. They could be used in the heterosis breeding for developing of high productive maize hybrids. The line KC 08 17 has both high GCA and SCA and can be used in corresponding breeding programs.