A clinical significance of the aberrant expression of HLA class I molecules including HLA class I and HLA-G was analyzed using tissue array analysis. Our institute has established a two millimeter spot sized tissue array set of 105 clinical cases of resected human non small cell lung cancer tissues. A loss of HLA class I was observed in the 58.3% of cancer tissues. The aberrant expression of HLA G was also observed in the 55.2% of cancer tissues. Statistically significant correlations were observed among HLA class I expression and tumor size, nodal involvement and pathological stage. Survival analyses were shown that the HLA class I loss was correlated to a recurrence free survival time. The HLA-G expression did not correlate with any clinico-pathological parameters. A loss of HLA class I was probably involved due to a cancer progression in human non-small cell lung cancer through the mechanism of immune escape from the host immune system.