Four tobacco varieties (three oriental and one semioriental) and their diallel hybrids from F₁, F₂ and BC₁ generations were investigated during 1997, in order to study the characters: height of the stalk, number of leaves per stalk and dry mass yield per stalk. The experimental design was a randomized block system with four replications in the research field of the Tobacco Institute in Prilep. Using the real average values of the parents and F₁ hybrids, with given formulas, the middle values of the studied characters in F₂and BC₁ back-cross generations were calculated, and comparison has been done between theoretically obtained results and the real ones which represent middle values of 200 measured individuals. It has been concluded that the theoretical values are very close to the real ones. In F₂ , BC₁ (P₁) and BC₁ (P₂) generations, degradation of the hybrid was noticed, which could be seen from the standard deviation and variability that were higher compared to those of the parents and F₁ hybrids. So, according to this, selection can be done from these generations.