Acute cholecystitis needs to be rapidly diagnosed and treated correctly. The classic patient characteristics were obese, increasing age, and being female. In a few cases, cholecystitis can occured in an atypical patient, such as in young age. Here, we report a 25-year-old obese female patient that came with right upper abdominal pain which was associated with nausea and vomiting. From imaging studies, we found that she had distended gallbladder with multiple stones. Open cholecystectomy was done and patient did well postoperatively. Acute cholecystitis had to be suspected in all age, especially in patient with another risk factor like obesity in our case. Keywords: acute cholecystitis, gallstone, cholecystectomy