A new human esophageal cancer cell line (YES-2) was established from a surgical specimen obtained from an 81-year-old male potient. This cell line has been maintained for 68 months through 196 passages. YES-2 cells have clear polygonal shaped cytoplasm, round nuclei and prominent nucleoli. The cells proliferate in a pavement-like cell arrangement and show a lack of contract inhibition. The doubling time at the 102nd passage was 23.7 hours. YES-2 cells produce squamous cell carcinoma antigen (SCC antigen), tissue polypeptide antigen (TPA) and carcinoantigen 125 (CA 125) as tumor markers. Chromosome analysis has shown that the chromosome number ranges from 53 to 62 with a mode of 60. Tumorigenicity has been demonstrated by development of tumor after the subcutaneous injection of YES-2 cells into nude mice. These findings indicate that the YES-2 cell line is a new human esophageal cancer cel line which may be useful for various studies