Insulin-like growth factors (IGF), regulated by their receptors and binding proteins, play a pivotal role in human cell proliferation, differentiation and apoptosis. Increasing evidence has revealed that IGF system is involved in the genesis and progress of various malignancies including lung cancer. Recent studies in regard to IGF axis expression in the lung cancer cell lines, pulmonary tissue samples and blood circulation of lung cancer patients have shown that the IGF axis may contribute to the transformation and progression of lung cancer. Several researches have shown that a number of drugs targeting the IGF receptor are being investigated in clinical trials and suggest a potential therapeutic efficacy. This article reviews the updates and progress in the research of IGF axis in lung cancer.