Histone deacetylases (HDACs) play a crucial role in tumorigenesis, however, the expression status of HDACs in lung cancer tissues has not been reported. We have investigated that HIDAC 1 mRNA levels and other clinico-pathological data, including MTA 1 mRNA expression in lung cancer. The study included 102 lung cancer cases. The HDAC1 mRNA levels were quantified by real time reverse transcription-polymerase chain reaction (RT-PCR) using LightCycler (Roche Molecular Biochemicals, Mannheim, Germany). The HDAC1/GAPDH mRNA levels were not significantly different in tumor tissues from lung cancer (30.654 +/- 33.047) and adjacent non-malignant lung tissues (18.953 +/- 56.176 , P = 0.1827). No significant difference in HDAC1/GAPDH mRNA levels was found among age, gender, and lymph node metastasis. The HDAC1/GAPDH mRNA levels were significantly higher in stage III or IV lung cancer (50.929 +/- 120.433) than in stage I lung cancer (11.430 +/- 25.611, P = 0.0472). HDAC1/GAPDH mRNA levels were significantly higher in T3 or T4 lung carcinoma (54.326 +/- 127.018) than in T1 or T2 lung cancers (14.790 +/- 48.670, P = 0.1601). HDAC1/GAPDH mRNA levels were correlated with MTA1/GAPDH mRNA levels (y = 0.0106x + 2.5827 , P = 0.0352 ). HDAC1/GAPDH mRNA levels were also correlated with HDAC1 protein (P = 0.0484) expression by immunohistochemistry. Using the LightCycler RT-PCR assay, the HDAC1 gene expression might correlate with progression of lung cancers. However, further studies are needed to confirm the impact of HDAC1 for the molecular target of the lung cancer.