Several double ALK fusions coexisting in one patient have been reported. However, few studies have reported the clinical efficacy of ALK inhibitors in rare double ALK fusions. Here, we described a rare PDK1-ALK, STRN-ALK double-fusion variant in a patient with metastatic lung adenocarcinoma. The patient responded well to alectinib (600 mg) twice daily. This case shows a promising treatment option for patients with rare ALK double-fusion variants.