Spontaneous regression of a lung cancer (SRC) is an exceptional event, within the extreme rarity constituted for the SRC in general. It's defined as the partial or total disappearance of a histological confirmed malignant tumour, without definitive treatment. The mechanism of the SRC remain in the dark, although the most of explanations are referenced to non specific stimulation of the immune system. We report the case of a patient with histological diagnosis of lung adenocarcinoma (T2, N1, M0) and with the necessary criteria of SRC.