Eight malignant and nine benign salivary gland neoplasms were cultured using a soft agar technique. Eleven of these tumors were successfully grown, two were contaminated, and only four demonstrated no growth. Cloning efficiency varied from 0.004% to 0.225%. These efficiencies and the 65% successful growth rate are much higher than those reported for head and neck squamous cell carcinomas. Single cell disaggregation with resultant clonal growth can be accomplished with salivary gland neoplasms. Ultrastructural study of colonies from three mixed tumors did not demonstrate distinct epithelial and mesenchymal populations of cells, the expected finding if mixed tumors were composed of two independent cell lines. Rather, mixed tumors invariably consisted of a monoclonal population of cells with evidence of ambivalent, mesenchymal, and epithelial differentiation. Myoepithelial cells were not present.