Dioxin contamination remains a serious and persistent environmental issue in Vietnam, especially at historical hotspots such as Phu Cat Airport. This study investigated the taxonomic and functional diversity of microorganisms inhabiting hotspots long-term dioxin-contaminated soil using metagenomic sequencing and enrichment-based isolation approaches. Shotgun metagenomic sequencing generated 50,349,630 high-quality reads, of which 12.81% were taxonomically classified, revealing 39 phyla dominated by Pseudomonadota (34.19%), Actinomycetota (14.61%), Planctomycetota, and Bacillota. Through three successive enrichments in mineral medium containing dioxin-contaminated soil extract, microbial cell density increased from 10³ CFU/g in the original soil to 10⁷ CFU/mL in enrichment cultures, while diversity decreased, reflecting selective adaptation to pollutant stress. Twenty bacterial strains were successfully isolated and grouped into nine distinct morphological types. Based on 16S rRNA gene sequencing, these isolates were assigned to eight genera within three phyla: Rhodococcus, Microbacterium, and Paenarthrobacter (Actinomycetota); Bacillus and Niallia (Bacillota); and Pseudomonas, Stenotrophomonas, and Vitreoscilla (Pseudomonadota). Among them, Rhodococcus ruber, R. phenolicus, and Pseudomonas sp. showed growth in medium containing 5% soil extract (TEQ measured prior to filtration: 604.6 pg TEQ/mL), indicating tolerance to dioxin-associated selective pressure. Comparative analysis of metagenomic and culture-based data revealed consistent dominance of Pseudomonadota and Actinomycetota, confirming their ecological importance and tolerance under long-term dioxin stress. The findings suggest that dioxin exposure may have influenced the formation of a phylogenetically diverse microbial community detected in the composite soil sample collected from the contaminated area. The combined use of culture-based and metagenomic methods offers preliminary insights into the indigenous microbial community and serves as a starting point for future studies aimed at determining whether these bacteria possess functional traits relevant to the bioremediation of persistent organic pollutants in Vietnam.