Alectinib is a key drug for treating ()-positive non-small-cell lung cancer (NSCLC). Alectinib-induced hepatotoxicity is less common than that through other ALK inhibitors, such as crizotinib or ceritinib. Herein, we describe a case of -positive adenocarcinoma successfully treated with lorlatinib after developing alectinib-induced hepatotoxicity. A 57-year-old Japanese man received alectinib as first-line therapy for -positive NSCLC. After 79 days, alectinib was discontinued because of hepatotoxicity and later restarted at 150 mg/day, inducing hepatotoxicity again after 64 days. Switching to lorlatinib treatment (continued for >4 months) caused no severe adverse effects. Hence, lorlatinib may be useful for patients experiencing alectinib-induced hepatotoxicity.