A biological characterization of tumor tissue is mandatory in NSCLC patients to identify cases at high risk of recurrence and to drive current targeted therapies such as EGFR and ALK inhibitors. In addition, promising results have been reported on the utility of molecular parameters for the prediction of the efficacy of systemic cytotoxic therapy. MicroRNAs (miRNAs) are small single stranded non-coding RNA molecules, which regulate gene expression at the posttranscriptional level. Growing evidence suggests that miRNAs are expressed aberrantly in many human cancers and that they play a significant role in carcinogenesis and cancer progression. There is increasing evidence that miRNA profiling may become an accurate way to differentiate tumor subtypes, determine prognosis and response to therapy. This review aims to summarize the current literature on this rapidly evolving field.