This study aimed to characterize the draft genome of Arthrospira platensis NH isolated in Vietnam and evaluate its phylogenetic position within cyanobacteria. Phylogenetic analysis based on 16S rRNA gene sequences confirmed that A. platensis NH belongs to the Arthrospira clade. The assembled genome comprises 5,548,511 bp and contains 4728 genes, including 4683 protein-coding sequences, 42 tRNA genes, and 3 rRNA genes. Genome mapping revealed conserved gene organization with an overall GC content of 44.45%. A comparative genomic analysis with other Arthrospira strains (A. platensis NIES-39 and C1) demonstrated high sequence conservation, supporting their close genetic relationships. Secondary structure prediction showed that all 42 tRNA types adopt typical cloverleaf structures, while the ribosomal RNA genes (16S, 23S, and 5S rRNA) exhibit conserved base composition. An analysis of 16S rRNA sequences from 13 cyanobacterial taxa identified 230 polymorphic sites, providing informative markers for phylogenetic divergence among genera. Collectively, these results establish a comprehensive genomic and phylogenetic framework for A. platensis NH and provide insights into its genetic relationships and potential biotechnological applications.