Abstract: The pseudostem weevil Odoiporus longicollis being a major pest of banana confers a serious loss to the crop. The cellulose- and terpene-laden diet demands a high reliance on gut microbiome to platter the nutrition. Here we investigated the whole microbiome of foregut, midgut and hindgut of O. longicollis to understand the spatial distribution of microbes. In bacteria, Firmicutes: Bacilli dominated the foregut and Proteobacteria: Gammaproteobacteria was highest in midgut and hindgut. Interestingly, Erysipelotrichia was comparatively much higher in hindgut. The Enterobacteriaceae subjugated the entire gut (Klebsiella and Enterobacter) with differential distribution of Raoultella, Citrobacter and Escherichia. This is followed by Lactobacillaceae (Leuconostoc, Lactiplantibacillus etc.) in foregut and Streptococcaceae (Lactococcus) in midgut and hindgut. The primary endosymbiont Candidatus Nardonella was found to be foregut-specific. In Fungi, Ascomycota and Basidiomycota were abundant. Foregut and hindgut had an abundance of Debaryomycetaceae (Scheffersomyces, Millerozyma and Candida) and the midgut had Saccharomycodaceae (Hanseniaspora and Yarrowia). Other eukaryotes i.e., Alveolata, Apicomplexa, Oomycota, Discoba, Amoebozoa, CS clade, Euglenozoa, Heterolobosea and Perkinsozoa were distributed differentially. Hindgut was determined to be a species-rich and diversified site for whole microbiome whereas for Fungi, foregut and midgut were species-rich sites, and hindgut and foregut had higher species diversity. Varying patterns of gene counts for carbohydrate metabolism, terpene degradation and nitrogen cycle were observed with particular significance in uncovering dependent and independent modes of cellulolysis in O. longicollis. The findings improved the understanding of site-specific diversity and richness of gut microbiome in O. longicollis to prospect for its control and management.