An in vivo model for human melanoma was established with the growth and metastasis of SK-MEL-2 cells. The tumor was introduced into C.B-17 SCID(severe combined immunodeficiency) mice intraperiotneally subcutaeously and intravenous inoculations. Tumors developed in 100% of mice inoculated subcutaneously and intraeritoneally both at site of inoculation and as metastatic tumor in the liver lungs and diaphragm. With intravenous inoculation 50% of mice showed metastasis in the spleen. Additionally metastatic foci that were not detected either by gross and/or standard histopathologic examination were demonstrated in the spleen and lungs by immunohistochemistry with HMB-45 monoclonal antibody. We conclude that the SCID mouse supports growth and metastasis of human malignant melanoma SK-MEL-2 cells.