Septoria tritici (Rob. et Desm.), cause of leaf blotch of wheat (Triticum aestivum L. em. Thell.) exhibited cultural variability into the nine cultures isolated. The cultural variability was observed into the same generation and furthermore into members of different generations of cultures. Cultures from field collection of S. tritici were established from single spore transfers on C ZD V’8 and APS. Produced stromatic and pycnidial colonies. Some cultures of pycnidial type show a marked tendency to produce mycelial type variants. Moreover, other cultures o f pycnidial type show stability. The variable cultural characters were: colour, area, mycelial structures, growth speed, sporulation. The saltation was very common into the cultures after some transfer generations. They dominated on C ZD V ’8, moreover, they were produced on all nutritive media. Only one culture was returned to original type with loss of sporulation.