The influence of salicylic and salicylhydroxsamic acid on in vitro potato plants growth was examined. Both solutions in higher contentrations (10-6, 10-7 mol dcm-3 SAL and 2 x 10-6, 2 x 10-7 mol dcm-3 SHAM) inhibited the growth of the shoots and the number of the leaves and roots. Lower concentrations (10-8 and 2x10-8 mol dcm-3), however, stimulated these processes. The inhibition and stimulation effects on cultivar 'Irga' and 'Irys' were observed. The intensity of tuberization was lower on the medium with the studied acids than in the control cultures. The level of linolenic acid was higher in plants with tuberizing potatoes. It suggests the inhibition of biosynthesis of the jasmonic acid (the stimulus of tuberization) by linolenic acid.