Six natural populations of sweet clover (Melilotus officinalis) were examined for allelic frequencies at 7 electrophoretically detected polymorphic loci in five enzyme systems: LAP, AP, ME, EST and PX. According to Nei’s statistics, the extent of genetic variability in all populations shows that intra-population genetic variability is expressed by higher values of GST coefficient (mean value for all loci 0.135) which exceeds values of inter-population differences expressed by DST=0.059 coefficient. Gene flow between populations is rather low (Nm=1.60). Hierarchical clustering (UPGMA) of Hedrick’s genetic distances (when examined simultaneously in all the allozymes), demonstrated three groups of populations suggesting certain tendency to geographic connections.