Locoregional treatment modalities for hepatocellular carcinoma are generally effective and safe and benefit the subset of patients who are not eligible for surgery or have marginal hepatic function. This case report discusses a 77-year-old patient with cirrhosis who underwent microwave lesion ablation for 3 hepatocellular carcinoma nodules. On the 12th day after ablation, the patient was diagnosed with a perforation of the anterior wall of the stomach near one of the target ablation sites on the left side of the liver. The patient underwent surgical therapy with clinical improvement. This report highlights the potential risks associated with microwave ablation for hepatocellular carcinoma.