The influence of chosen saccharides on the growth and development of the in vitro shoot cultures of Paulownia tomentosa – valuable and multi-purpose tree species. The mainly sucrose (10–50 g dm^-3), glucose and fructose (15.8 and 30 g dm^-3) were tested in three subsequent passages. Then the usefulness of saccharides in different applications of in vitro cultures was assessed. The basic MS medium supplemented with BA (1 mg dm^-3), NAA (0.1 mg dm^-3), and GA₃ (0.1 mg dm^-3) was used. Saccharides in tested concentrations influenced development of in vitro cultures. Proliferation of axillary shoots remained comparable whereas the development of adventitious shoots significantly and the frequency of vitrification decreased while the concentration of sucrose increased from 20 to 40 g dm^-3. Glucose (15.8 g dm^-3) stimulated both proliferation and elongation of axillary shoots. Sucrose (10 g dm^-3), and fructose (15.8 g dm^-3) favoured development of adventitious shoots and vitrification of cultures. The media supplemented with sucrose (30–40 g dm^-3) or glucose (15.8 g dm^-3) may be recommended for micropropagation of true-to-type plants, whereas sucrose (50 g dm^-3), and fructose (15.8 g dm^-3) for long term storage, and plant breeding, respectively.

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