Portal vein thrombosis can occur after laparoscopic operations. This complication has not been yet reported after laparoscopic sleeve gastrectomy. We report the case of a patient who presented mild abdominal pains 2 weeks after a laparoscopic sleeve gastrectomy achieved to cure morbid obesity. Computed tomography led to the diagnosis of portal vein thrombosis bound to a genetic disorder due to heterozygote Leiden 2 factor which impaired coagulation. Recommendations for post-surgical follow-up are discussed.