The beetles, members of the Order Coleoptera are the largest order of insects, with about 40 % of known species of total insect world or about 400,000 species. My first edition of this book was published in 2002 and was also the first book of beetles available in Thailand. This is a revised edition, emphasizing the species content and possibility of additional species for all those beetle families, this edition contains 509 species as compared to the first edition which included only 362 species and subspecies.