Pulsatilla vernalis is a rare species in the Polish lowlands, strongly threatened by anthropogenic disturbance of its habitats. A grave decrease in its populations has been observed during the past 60-80 years (analogous populations in Eastern Austria and the Czech Republic are almost or completely extinct). An analysis of the genetic diversity of populations in the Polish lowlands was performed to estimate its level and distribution. The AFLP method was used for the study of seven populations. An analysis using five pairs of selective primers revealed 446 scorable fragments; 62.1% of them were polymorphic. The average gene diversity indices was 0.17 (the mean value for all the populations), ranging from 0.139 to 0.204. A weak relationship between diversity and population size was revealed. Most of the genetic diversity was contributed to by the within-population level (AMOVA) and only a weak geographical structure was shown by UPGMA clustering. Four populations formed population-specific clusters while three others (from one region) were intermixed. These preliminary results show a moderate genetic diversity of the studied populations, which was still rather high when compared with their size. This result, together with the low between-population differentiation in the region, suggests that these populations are the remnants of larger populations that, only a few decades ago, were much less isolated.