Epigenetic is the study of heritable changes in gene expression that occur without changes in DNA sequence. This process is important for gene expression and genome stability and its disruption is now thought to play a key role in the onset and progression of numerous tumor types. The most studied epigenetic phenomena includes post-translational modifications in DNA and histone proteins as well as microRN As expression. As epigenetic aberrations are potentially reversible, their correction has emerged as a potential strategy for the treatment of cancer. This review highlights the roles of chromatin epigenetic modifications and of microRN As expression in lung tumorigenesis and discusses the emerging epigenetic therapies which are being developed for the treatment of lung cancer.