Abstract Background To compare the efficacy of crizotinib, pemetrexed and other chemotherapy regimens as a first-line treatment in patients with anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC) in real world clinical use and to evaluate the +86–571-87,236,876 predictive clinical factors of the efficacy of crizotinib. Methods The 73 patients with ALK-positive advanced NSCLC were divided into three groups based on the first-line treatment: first-line crizotinib group (1-CRZ group, n = 32); first-line platinum-based pemetrexed treatment group (1-PP group, n = 28), and first-line chemotherapy platinum-based non-pemetrexed group (N1-PP, n = 12). Sixty eight of the 73 patients received crizotinib treatment and followed up in our hospital. Differences in the objective response rate (ORR), disease control rate (DCR) and progression-free survival (PFS) were compared in the different groups. The clinical factors were evaluated to predict the efficacy of crizotinib by the Kaplan–Meier survival analysis and Cox proportional hazards model. Results The PFS, ORR, DCR were 16.1 months, 78.1% (25/32) and 100% (32/32) in the 1-CRZ group; were 6.0 months, 17.9% (5/28) and 57.2% (16/28) in the 1-PP group; and were 2.9 months, 15.4% (2/13) and 46.2% (6/13) in the N1-PP group. The PFS of the 1-CRZ group was significantly longer than that of the 1-PP group (P = 2) (HR 2.345, 95% CI 1.137–4.834, P = 0.021) and patients received crizotinib after N1-PP chemotherapy (HR 2.345, 95% CI 1.137–4.834, P = 0.021) were two factors associated with shorter PFS after crizotinib treatment. Conclusions In patients with ALK-positive NSCLC who did not receive previous treatment, crizotinib was superior to standard chemotherapy for the longer PFS and greater ORR and DCR. Higher ECOG score (> = 2) and patients received crizotinib after N1-PP chemotherapy predict poor efficacy of crizotinib.