The DNA of Rickettsia provazekii strain E was cleaved by PstI restriction endonuclease under the conditions of partial restriction. The fragments were inserted into the PstI site of pBR325 and cloned in this plasmid. E. coli strain HB101 was used as a recipient for cloning. 880 clones sensitive to ampicillin and resistant to tetracycline were selected from 5120 transformants. The cloning of rickettsial DNA has been confirmed by the blot hybridization technique. Analysis of individual and net probes of the hybrid DNA by gel electrophoresis makes it possible to conclude that 90% of the selected clones harbour hybrid plasmids, the size of the cloned fragments rangers from 0.9 to 10.4 Kb, the obtained library of clones contains 70% of the whole genome of Rickettsia provazekii.