Microbial forensics is an emerging discipline that integrates microbiological and molecular approaches to support forensic investigations. The human microbiome—comprising diverse, individualized, and relatively stable microbial communities—offers promising potential as a biological identifier. Among its applications, bloodstain microbiome analysis provides a valuable avenue for cases where conventional DNA evidence is degraded, limited, or unavailable. This chapter explores the forensic relevance of bloodstain microbiome profiling, with emphasis on its utility in postmortem interval (PMI) estimation, source attribution, and individual discrimination. Recent advancements in next-generation sequencing (NGS), metagenomics, and bioinformatics are reviewed, along with standardized workflows for sample collection, DNA extraction, 16S rRNA sequencing, and computational analysis. Experimental studies simulating environmental and temporal influences on bloodstains are also discussed. Bloodstains demonstrate characteristic microbial succession patterns that change over time and are shaped by environmental variables such as temperature, humidity, and substrate. These dynamic microbial shifts can be quantified to support PMI estimation, differentiate human from nonhuman blood sources, and associate individuals with specific environments. Despite encouraging progress, challenges related to standardization, contamination control, and database limitations remain. Bloodstain microbiome analysis holds significant promise for advancing microbial forensics by extending the evidentiary value of biological samples and offering novel parameters for forensic interpretation. Continued integration of multiomics technologies, AI-driven analytics, and robust reference databases will be essential for its transition into routine forensic practice.