•Brain metastases are common in ALK-positive NSCLC and impact patient (pt) QoL.•Overall improvement/delayed deterioration in QoL seen with lorlatinib or crizotinib.•Numerical improvements favor lorlatinib in most functioning and some symptom scores.•PROs were similar in lorlatinib-treated pts with/without baseline brain metastases.•Improvements in PROs, and efficacy data, support use of lorlatinib over crizotinib. Quality of life (QoL) for patients with non-small cell lung cancer (NSCLC) is negatively impacted by their disease and treatment side effects. We present detailed patient-reported outcome (PRO) data from the phase 3 CROWN study, which compared lorlatinib with crizotinib in patients with previously untreated ALK-positive advanced NSCLC. PROs were assessed using the European Organisation for Research and Treatment of Cancer QoL Questionnaire with Lung Cancer module. A longitudinal, random-intercept, random-slope, mixed-effect model assessed score changes from baseline up to (not including) end of treatment. Mean changes of absolute scores from baseline at each cycle were calculated and presented up to cycle 18 (≥ 10-point change considered clinically meaningful). In both lorlatinib (n = 148) and crizotinib (n = 140) arms, there were longitudinal improvements across multiple functioning and symptom scores during treatment compared with pre-treatment. Numerical improvements for most longitudinal functioning scores (physical, role, emotional, social) favored lorlatinib; cognitive functioning favored crizotinib. Numerical improvements favored lorlatinib for several symptoms (fatigue, nausea and vomiting, insomnia, appetite loss, constipation, diarrhea clinically meaningful improvement, and cough); peripheral neuropathy favored crizotinib. Subgroup analyses showed PROs did not differ by presence/absence of baseline brain metastases. Patients receiving first-line lorlatinib or crizotinib showed improvements and delayed deterioration in QoL, functioning, and several symptoms. Alongside the previously reported significantly longer progression-free survival and higher intracranial response rates for lorlatinib versus crizotinib, these data further support the use of lorlatinib over crizotinib in patients with advanced ALK-positive NSCLC with/without baseline brain metastases and provide evidence of several QoL improvements with lorlatinib when used in the first-line setting.