Taken together, our pan-cancer analysis showed that the expression level of PCSK9 was significantly correlated with clinical characteristics, prognosis, immune matrix score, immune cell infiltration, immune checkpoint expression, and major histocompatibility complex expression in patients with multiple tumors, which is helpful for understanding the role of PCSK9 in tumorigenesis in various cancers from the perspective of clinical data. Here, PCSK9 is linked to cancer.