Since the first case of corona virus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the end of 2019, the virus has spread rapidly around the world and has become a global public health problem. In the process of this virus epidemic, compared with the general population, cancer patients are considered to be highly susceptible people, especially the lung cancer patients. Some studies have shown that angiotensin converting enzyme 2 (ACE2) may be the pathway for SARS-CoV-2 to infect the host. At the same time, ACE2 is often abnormally expressed in non-small cell lung cancer. Therefore, understanding the respective mechanisms of ACE2 in COVID-19 and non-small cell lung cancer has extremely important reference value for the study of vaccines and therapeutic drugs, and also provides meaningful guidance for the protection of patients with lung cancer during the epidemic. This article reviews the possible invasive mechanism of ACE2 in SARS-CoV-2 and its abnormal expression in non-small cell lung cancer.