Diverse array of yeasts are associated with Coleopteran beetles in forest.Some yeasts are apparently involved in the life history of beetles, albeit with less scientific attention compared to those for associated filamentous fungi.Yeasts must be important but neglected members inhabiting in the forest ecosystems.In this presentation, yeasts associated with Coleopteran beetles in forest, with a special emphasis on beetles belonging to the family Platypodidae in Japan, are introduced and discussed in the context of yeast-beetle symbiosis.