The influence of carbon and nitrogen sources on the production of xanthan gum and extracellular enzymes by penicilineresistant mutant of Xanthomonas campestris was investigated. The good carbon sources for xanthan production were maltodextrin, sucrose, glucose, celobiose, inulin and maltose. The highest xanthan concentration was obtained after cultivations in the presence of 3% addition of maltodextrin and sucrose. Also, the high activities of extracellular enzymes (inulinase, invertase, α – amylase) were estimated in the media. The best nitrogen sources for xanthan production by X. campestris were (NH₄)₂SO₄ and urea.