An 84-year-old man diagnosed with Budd–Chiari syndrome (BCS) developed a 20-mm hepatocellular carcinoma. We performed laparoscopic hepatectomy without complications, but the patient's percutaneous oxygen saturation gradually worsened and pulmonary edema was detected 50 minutes after extubation. He was subsequently re-intubated and received diuretic therapy. He was discharged on postoperative day 32. Patients with severe BCS have been reported to have an expanded plasma volume. In addition, pneumoperitoneum during laparoscopic surgery has been reported to decrease the venous flow in the portal vein and/or renal vein, the collateral pathways in BCS. The cause of pulmonary edema in the present case may have involved increased venous return following decompression of pneumoperitoneum pressure under the state of an expanded plasma volume. This case suggests that clinicians should pay special attention to achieving volume control in patients with BCS, particularly during laparoscopic surgery and minimizing the duration of pneumoperitoneum.