Inflammatory myofibroblastic tumor (IMT) is a rare cancer that is most commonly found in children and young adults, and it is usually detected in the lungs and abdomen. IMT is often associated with an anaplastic lymphoma kinase (ALK) gene rearrangement. We report the case of a 17-year-old male with ALK positive intracranial IMT managed with surgical resection and entrectinib, an ALK inhibitor. This case shows the importance of gene sequencing in diagnosing central nervous system (CNS) tumors and the promising role of ALK inhibitors in IMT treatment. Hypersensitivity to alectinib resulting in successful substitution to entrectinib was also noteworthy.