Our institution has been working on examination of basic characteristics of flue-cured tobacco for five years. The main elements of the research work are the following: measurement of thermal features, monitoring the colour-changes and examination of some physical parameters. In the present stage we analyse the most important chemical components (carbon hydrate, total nitrogen, reducing sugar, nicotine). The evaluation of some chemical components has proved, that there is a close relation between the quality categories and the chemical characteristics of flue-cured tobacco. The amount of reducing sugar and total nitrogen has varied considerably, according to the curing schedules. The value of nicotine has not changed significantly. It means, that we can not influence so much the nicotine - content by the curing technology. There has been another conclusion, that the quality has altered between the difference maturing levels. In Hungary it is very important to improve the quality of the cured tobacco. The suggested curing schedule could add to this requirement.