Abstract: A freeze-etching study of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) waa made. There were relatively uniform cells and nuclei, less nuclear pores, less cytoplasmic organelles, prominent tight junctions and rare gap junctions (GJ) in BCC. But there were irregular shapes of cells and nuclei, more nuclear pores, rich cytoplasmic organelles, widened intercellular spaces and increased GJ in SCC. The authors discussed with laboratory studies that malignant tumors did not always lack GJ, they were different, in various types of malignant tumor. More or less GJ seemed to be related to the activity of cells and metabolism. In SCC it was shown there were hyperactivity of cells and increased metabolic activity: In BCC the low invasion and rare metastasis might be related to its prominent tight junctions and less cytoplasmic organelles.