The vertebrate genome contains an endogenous retrovirus that were inherited parts from millions of years ago. Although approximately 8% of human chromosomal DNA consists of sequences derived from human endogenous retrovirus (HERV) fragments, most HERVs are currently inactive and non-infectious due to recombination, deletions and mutations after insertion into host genome. Several studies suggested that Human endogenous retroviruses (HERVs) factors are significantly related with certain cancers. However, only limited numbers of studies have been conducted to analyze the expression of HERV derived elements at protein levels in certain cancers. Herein, we analyzed the expression profiles of HERV-K envelope (Env) and HERV-R Env proteins in eleven different kinds of cancer tissues. We also analyzed the expression patterns of both protein and correlation with various clinical data in each individual tissue. The expressions of both HERV-K Env and HERV-R Env protein were significantly high in most tumors comparing with normal surround tissues. Correlations between HERV Env expressions and clinical investigations varied depending on HERV types and cancers. Overall expression patterns of HERV-K Env and HERV-R Env proteins were various in each individual but showed similar pattern between HERV-K Env and HERV-R Env in same individual. These studies show the expression profiles of HERV-K and HERV-R Env proteins in various cancer tissues and provide a good reference for the association of endogenous retroviral Env proteins in various cancer progression. Furthermore, the results elucidate the guideline of the relationship between HERV-Env expressions and clinical significance of certain cancers.