Objective:To investigate the expression of autophagy related gene; Beclin1 in human non-small cell lung cancer(NSCLC) tissues. Methods:Protein expression of Beclin1 was determined by immunofluorescence staining and Western Blot, mRNA expression was analyzed by RT-PCR. Results:Immunofluorescence staining revealed that the level of Beclin1 expression in lung cancer was significantly lower than that in adjacent noncancerous tissues and normal tissues(expression rate 8.3%, P=0.000). The Beclin1 mRNA expression in lung cancer, adjacent noncancerous tissues and normal tissues was 1.372 (±0.475) 1.721 (±0.521) and 1.553(±0.554) when F = 15.0, P < 0.01. Beclin1 protein expression in lung cancer, adjacent noncancerous tissues and normal tissues was 3.453(±0.852) 5.423(±1.351) and 6.878(±0.997) F = 11.2, P < 0.01. Conclusion:The protein and mRNA expression of Beclin1 in lung cancer was much lower than those in and around cancer tissues and normal tissues, those differences having statistical significance. However in adjacent noncancerous tissues and normal tissues, the expression showed no difference.