The　goal　of　person　re-identification　(ReID)　is　to　retrieve　a　specific　person　between　multiple　non-overlapping　cameras.　Representative　deep-learning-based　person　ReID　methods　were　reviewed　and　the　architectures　and　features　of　different　person　re-identification　methods　were　discussed　in　this　paper.　First,　the　definition　of　person　ReID　was　introduced.　Second,　supervised　learning　methods　and　weakly　supervised　learning　methods　were　reviewed,　respectively.　In　particular,　The　feature　representation　learning　and　metric　learning　of　the　supervised　learning　methods　were　discussed　in　detail.　Third,　the　mainstream　datasets　in　different　tasks　were　analyzed,　and　the　state-of-the-art　methods　were　evaluated　and　compared.　Finally,　important　yet　under-developed　research　directions　were　briefed.　©　2022,　Editorial　Department　of　Journal　of　Beijing　University　of　Technology.　All　right　reserved.