ObjectiveTo explore the expressions of glucose regulated protein (GRP) 78 and GRP94 in rectal adenocarcinoma and their clinical significances. MethodsIn 45 paraffin-embedded sections of rectal adenocarcinoma tissues and adjacent normal tissues, the expressions of GRP78 and GRP94 were examined by EnVisionTM. ResultsThe positive rates of GRP78 and GRP94 protein expression in the rectal adenocarcinoma tissues were 53.33% (24/45) and 53.33% (24/45), while those in the adjacent normal tissues were 13.33% (6/45) and 15.56% (7/45), respectively. There was a statistical significance of the expression of GRP78 or GRP94 between the tumor tissues and the adjacent normal tissues (all P < 0.001), and it was found that the positive expression rates were relevant to the extent of differentiation, Dukes stage, and lymph node metastasis of cancer (all P < 0.05), but not to the patient's sex, age, and size of tumor (all P > 0.05). And there was a statistical significance in Spearman method about the rate of positive expression between GRP78 and GRP94 (rs=0.464, P < 0.01). ConclusionGRP78 and GRP94 protein is highly expressed in rectal adenocarcinoma tissue, related to its metastasis and invasion, might be used as a useful indicator to judge the malignant degree.