Abstract: Milky spots(MS) are widely located in mammalian peritonea and mainly composed of mesothelial cells, vascular endothelial cells, macrophages in different stages of maturation, B-lymphocytes, T-lymphocytes, mast cells and stromal cells. Peritoneal malignant tumor cells enter MS as they exfoliate from primary tumor lesions, colonize within them, and establish micro-metastasis, leading to peritoneal carcinomatosis(PC). This review summarizes the anatomy, histology, physiology and pathology of MS and explores the relationship between MS and PC.