"Objectives of this project are to determine genetic diversity of honey bees in the genus Apis using DNA barcoding technique, to analyze evolution of dwarf bee (Apis florea), eastern honey bee (A. cerana) and western honey bee (A. mellifera) by experiment on egg removal behavior of bees (worker policing) and to determine genetic differences of wax moths in the northeast of Thailand using DNA barcoding technique. Worker bees of the giant honey bee (Apis dorsata) were collected from Phu Pha Kood, Mukdahan province for genetic difference analysis with other species of honey bees in the genus Apis. Adult bees were used for DNA extraction, COI gene was amplified using PCR. The result showed intra-specific genetic distance among samples of 17 colonies from Phu Pha Kood was low, 0.7%. After compare with other 3 honey bee species, A. florea, A. cerana and A. mellifera, indicated that inter-specific genetic distances were 12.26%, 9.51% and 10.25%, respectively. COI was also used to investigate genetic difference among wax moths in the northeastern Thailand. The result shows that wax moth samples were divided into 2 groups, greater wax moth (Galleria mellonella) and lesser wax moth (Achroia grisella). Intra-specific genetic distances was 0.5% and 0.3%, respectively, while inter-specific genetic distance was 14.6%. This indicated that COI gene is suitable to use for DNA barcoding in both Apis honey bees and wax moths. Worker policing experiments were conducted in A. florea and A. cerana colonies using queen-laid eggs (QL) and worker-laid eggs (WL) of A. mellifera. The results showed that both A. florea and A. cerana workers could not significantly distinguish QL eggs from WL eggs of A. mellifera (P = 0.836 and 0.399, respectively). A. florea workers could eliminate all kinds of eggs faster than workers of A. cerana approximately 9 times, indicating that A. mellifera egg pheromones may be changed across evolutionary time. Egg pheromone of A. mellifera may be much more different from A. florea than A. cerana, then workers of A. florea could identify and eliminate eggs faster than A. cerana workers did. "