Plantain (Musa paradisiaca L.), Nigeria’s third most important starchy staple, depends on rhizosphere bacteria for nutrient acquisition and stress tolerance, yet its microbial profile remains underexplored. This study applied 16S rRNA amplicon sequencing to characterize bacterial diversity and GC content in plantain rhizosphere from Rivers State, Nigeria. Diseased plantain roots were collected from the Rivers State Institute of Agriculture Research and Teaching (RIART) Farm, Port Harcourt, Nigeria. Genomic DNA was extracted from plantain roots and amplicons sequenced following Laragen’s validated proprietary. The metagenomic data were analyzed using Laragen’s proprietary in-house pipeline based on BLAST searches for taxonomic classification. The results revealed that Proteobacteria dominated (54.81%), followed by Verrucomicrobia (16.48%), Bacteroidetes (12.28%), Actinobacteria (8.10%), and Planctomycetes (3.16%). Alphaproteobacteria (29.1%), Gammaproteobacteria (21.4%), and Rhizobiales (23.1%) were prevalent at class and order levels. Dominant genera included Luteolibacter sp. (14.5%), Pseudoxanthomonas sp. (14.5%), and Devosia sp. (13.8%), with unclassified taxa reaching 38.4% at genus/species levels. GC content varied widely (<30% to ~70%), highest in Gordonia sp. and Paracoccus sp., lowest in Paludibacter sp. and Pseudoxanthomonas sp. The study revealed marked genomic diversity in the rhizosphere of plantain. Future studies should use shotgun metagenomics, isolate key taxa, and develop targeted bioinoculants to improve plantain productivity and sustainability in Nigerian agroecosystems.