Objective To explore knowledge and beliefs of long‐term smokers about lung cancer, associated risk factors and lung cancer screening. Design Qualitative study theoretically framed by the expanded Health Belief Model based on four focus group discussions. Content analysis was performed to identify themes of knowledge and beliefs about lung cancer, associated risk factors and lung cancer screening among long‐term smokers' who had and had not been screened for lung cancer. Methods Twenty‐six long‐term smokers were recruited; two groups (n = 9; n = 3) had recently been screened and two groups (n = 7; n = 7) had never been screened. Results While most agreed lung cancer is deadly, confusion or inaccurate information exists regarding the causes and associated risk factors. Knowledge related to lung cancer screening and how it is performed was low; awareness of long‐term smoking's association with lung cancer risk remains suboptimal. Perceived benefits of screening identified include: (i) finding lung cancer early; (ii) giving peace of mind; and (iii) motivation to quit smoking. Perceived barriers to screening identified include: (i) inconvenience; (ii) distrust; and (iii) stigma. Conclusions Perceived barriers to lung cancer screening, such as distrust and stigma, must be addressed as lung cancer screening becomes more widely implemented. Heightened levels of health‐care system distrust may impact successful implementation of screening programmes. Perceived smoking‐related stigma may lead to low levels of patient engagement with medical care and decreased cancer screening participation. It is also important to determine modifiable targets for intervention to enhance the shared decision‐making process between health‐care providers and their high‐risk patients.