Cirsium pannonicum is a protected species in Poland. The sources of threats are both spontaneous successional changes in vegetation leading to overgrowth of xerothermic grasslands and human activity. Active methods of protection are therefore indispensable for preservation of the species. Micropropagation in an in vitro culture may be one of the useful tools to protect the species actively. The objective of present work was to develop an efficient system for C. pannonicum in vitro propagation and comparison of morphological traits and the ability to flower in plants obtained by micropropagation and from seeds. Isolated shoot tips from 10-day-old seedlings were cultured on MS medium supplemented with: 6-benzylaminopurine (BA), kinetin (KN) or zeatin (ZEA) at concentration of 1.0, 2.0 or 3.0 mg^.L^-1 in combination with naphthaleneacetic acid (NAA; 0.1 mg^.L^-1). The highest shooting frequency 93.6% and shoot multiplication rate 2.8 shoots/explant was obtained on medium supplemented with 2.0 mg^.L^-1 BA and 0.1 mg^.L^-1 NAA. In subsequent subcultures, average 3.3 axillary shoots per explant on MS with 3.0 mg^.L^-1 BA was recorded, the difference was not statistically significant. The highest rooting frequency 86.1% was observed on 1/2 MS medium. Regenerated plants produced leaf rosettes and inflorescence stems typical for this species. However, compared to plants developed from seeds, these were fewer, much shorter and contained a greater number of capitula on individual stems. In the first year after acclimatization into the field condition, approximately 64% of individuals flowered. During the next years, all plants flowered in a period typical for the species. The flowers were fertile and the seeds were viable.

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