Avery (1933) studied the growth of the whole tobacco leaf and some of its segments and concluded a different growth intensity of some of the leaf areas. But, the problems of a chemical heterogeneity of some leaf segments are of the extreme significance from the aspect of physiology and biochemistry. This significance is very important for some plant species like tobacco where a leaf represents the basic organ of the plant and is the reason for it to be grown (Tso, 1990). Our research work in chemical heterogeneity of some transversal and longitudinal leaf segments was done with maize, sugar beet and sunflower leaves. The results gained showed that the coefficient gradient of N, P, K, Ca and Mg was very different depending on the leaf segment. As mentioned above, this problem is extremely important for tobacco leaf studies. Tobacco leaf has been transversally divided on 12 segments and longitudinally on 9. Separately were divided parts of lamina, lateral veins and parts of midrib that belonged to some segments. For four (4) segments from the leaf periphery were separated towards the midrib and the midrib was taken out separately. In all segments mentioned, meaning the tobacco leaf parts, the concentration of N, P, K, Ca, Mg and nicotine, protein nitrogen, proteins and soluble sugars was determined. The results showed that the values gained from the tested parameters were different depending on the topography and the parts of the leaf segments. These results have not only theoretical significance referring the concentration of the tested substances but are also very significant for tobacco production and processing.