Triple-Negative Breast Cancer (TNBC) is known for its high recurrence and metastasis rates, posing treatment difficulties and a poor prognosis post-metastasis. Exosomes, linked to metastasis and immune evasion, could be early biomarkers for tumor spread. This study seeks to identify and preliminarily validate serum markers for diagnosing TNBC metastasis using high-throughput sequencing.