Ten species of ambrosia beetles of the tribe Xyleborini , Amasa beesoni (Eggers, 1930), Amasa opalescens (Schedl, 1937), Amasa cylindrotomica (Schedl, 1939), Arixyleborus hirsutulus Schedl, 1969, Beaverium latus (Eggers, 1923), Cnestus protensus (Eggers, 1930), Coptodryas quadricostata (Schedl, 1942), Cryptoxyleborus confusus Browne, 1950, Cryptoxyleborus percuneolus (Schedl, 1951) and Cyclorhipidion vigilans (Schedl, 1939), are recorded here for the first time in Thailand. Diagnostic characters, illustrations, distribution and biological data are provided for each species. Xylosandrus ramulorum (Schedl, 1957), stat. res. is removed from synonymy with Amasa cylindrotomica and reinstated as a valid species.