Cereal crops are the major staple food producers of the world. The global food security, therefore almost entirely depends on cereals. Insects play a vital role in cereal production system. Among the insects, beetles belonging to the Order Coleoptera are the single largest group in the whole of Animal Kingdom. Naturally, it is no surprise that beetles are the predominant insects in the cereal agroecosystems. The species diversity, morphology and intraspecific variations need a special focus to understand the ecological dynamics of pests and natural enemies within the cereal beetles group. Such understandings would greatly help in pest management decisions. Therefore, we in this book provided multivariate morphometric analysis of intraspecific variations and an exhaustive analysis of diversity of beetles.