Isolated monoclonal antibodies are disclosed herein that specifically bind endoplasmin In some embodiments these antibodies are fully human. Recombinant nucleic acids encoding these antibodies, expression vectors including these nucleic acids, and host cells transformed with these expression vectors are also disclosed herein. In several embodiments the disclosed antibodies are of use for detecting and/or treating tumors that express endoplasmin, such as melanoma, breast cancer, head and neck squamous cell carcinoma, renal cancer, lung cancer, glioma, bladder cancer, ovarian cancer or pancreatic cancer. In one example, the tumor is a melanoma.