Background: Real-world clinical outcomes of anaplastic lymphoma kinase positive (ALK+) non-small cell lung cancer (NSCLC) patients vary. This study aimed to investigate the treatment and clinical outcomes of all ALK+ NSCLC patients in Denmark in the period 2011–2018, regardless of disease stage. Materials and Methods: A national pathology database with complete coverage was used to identify ALK+ NSCLC patients diagnosed between 2011 and 2018. Clinical data were obtained through retrospective chart reviews. Overall survival (OS) and duration of treatment (DOT) were analyzed using Kaplan-Meier methodologies. Results: A total of 209 ALK+ NSCLC patients were included. The cohort had a slight overrepresentation of female patients (56.5%) with a mean age of 61.6 years. Most patients were adenocarcinoma cases (97%) and presented with an ECOG performance status of 0–1 (79%). Stage IIIb–IVb patients comprised 70% of the cohort. The use of ALK-tyrosine kinase inhibitors (TKIs) as first-line treatment increased over time, with the 1st generation ALK-TKI crizotinib being the predominant treatment in the 1st line. In 1st line treatment, 2nd generation ALK-TKIs had a median DOT more than twice the median DOT of crizotinib (25.1 and 9.1 months, respectively). The median OS for the entire cohort was 44.0 months. Patients with stage I–IIIA disease had a median OS that had not been reached, while those with stage IIIb–IVb disease had a median OS of 31.8 months. Patients with stage IIIb–IVb disease receiving an ALK-TKI as 1st line treatment had a median OS of 42.5 months with immature follow-up. Brain metastases at diagnosis or choice of 1st line treatment did not statistically significantly impact OS. Conclusion: This study gives insights into the treatment and outcome of ALK+ NSCLC patients in Denmark and provides a real-world confirmation of the superior disease control provided by 2nd generation ALK-TKIs as compared to the 1st generation ALK-TKI crizotinib.