A Bam HI cleaved 3.2 Kb fragment from the HBV adr genome was cloned in E. coli using pBR322 as vector. Sixteen restriction sites from the action of Bam HI, Hind III, Bgl I, Bgl II, Ava I, Hinc II, Sph I, Xba I, Xho I and Sst II were determined and mapped. No cleavage sites were found for Eco RI, Pst I, Sma I, Hpa I, Kpn I, Pvu II and Sst I. The restriction map for HBV adr is significantly different from those reported for the subtypes adw, ayw and adyw.