We characterized 23 isolates of the entomopathogenic fungus Aschersonia spp. from Mexico, Brazil, Guyana, Trinidad, Venezuela, Columbia, Florida, Malaysia, Thailand, Japan, Philippines, Java and South India using RAPD markers. The data were used to compute the genetic variability and to reconstruct the phylogeny of the genus Aschersonia. Relative genetic distances varied from 0.018 (between isolates Aa2 and Ap2) to 0.445 (between isolates A1 and At1). In the constructed phylogenetic tree, isolates were clustered according to their geographical origin. We determined partial 26S ribosomal DNA sequences of five Aschersonia isolates (A28, A31, Ai1a, Ai2b - Aschersonia spp.; and Ap1- Aschersonia placenta) and used them for phylogenetic analysis. Three of the tested isolates were not distinguishable. The tree constructed indicated that isolates Ai1a and Ai2b belong to species distinct from A. placenta and A. aleyrodis.