Objective To investigate the effect of fear of progression on psychological distress in advanced lung cancer patients and their spousal caregivers.Methods This was a cross-sectional study, and 240 dyads of advanced lung cancer patients and their spousal caregivers were selected using convenience sampling method.The Actor-Partner Interdependence Model (APIM) was used to analyze dyadic data obtained with the Kessler Psychological Distress Scale and the Fear of Progression Questionnaire-Short Form.Results The total scores of psychological distress among advanced lung cancer patients and their spouses were （31.53±6.60） and （32.37±6.49）, respectively.The scores of fear of progression were （35.55±8.79） and （37.26±6.34） in patients and their spouses respectively.Both actor and partner effects were found （both P＜0.05）.Higher fear of progression was related to more severe psychological distress in patients and caregivers.Conclusion Both patients and their spousal caregivers experience moderate to high level of psychological distress, which is affected by their own and partner′s fear of progression.Meical staff need to consider the patient-caregiver dyad as a unit of care, and identify their fear of disease progression as early as possible, to ameliorate the negative effect on psychological distress.