Two honeybee DNA methyltransferase genes have recently been identified and confirmed to be functional. The honeybee genes under regulation by DNA methylation may therefore be CpG deficient, due to natural deamination of methylated DNA. In this report, we show that <39% of the known honeybee genes are likely to be methylated on the basis of their low CpG obs/exp ratios. In contrast, orthologues of these genes in the fruitfly do not show CpG deficiency. Classes of function as determined by Gene Ontology were obtained for the honeybee genes with significantly low and high CpG obs/exp ratios. Overrepresented classes in the low CpG[obs/exp] genes are involved in transcription, translation, protein folding, protein localization, protein transportation, cell cycle, and DNA and RNA metabolism.