The absence of a small portion of the pericardium is termed pericardial defect. This rare entity can be either acquired or congenital. The prevalence of congenital pericardial defect is exceedingly rare, which is approximately 0.002-0.004% of surgical and pathologic series. The most common type is the absence of the entire left side of pericardium, seen in 67% of all patients with a congenital pericardial defect. Other varieties are incredibly uncommon. Congenital pericardial defect has a male preponderance with a male to female ratio of 3:1, and familial occurrence is uncommon. We report a case of left partial congenital pericardial defect detected incidentally in a 22-year-old man who presented with recurrent left spontaneous pneumothorax. He underwent video-assisted thoracoscopic bullectomy and intraoperatively, we discovered a left partial pericardial defect which exposed the left atrial appendage. Although generally asymptomatic, patients may present with non-specific cardiac symptoms such as atypical chest pain. Partial pericardial defects have an increased risk of herniation of the whole left atrium, the left atrial appendage or the ventricles. If this occurs, cardiac strangulation may occur, leading to necrosis and sudden death. Cardiac MRI is a sensitive tool and will demonstrate the absence of preaortic pericardial recess. In conclusion, no surgical intervention is required in cases of congenital pericardial defect, unless the patient is symptomatic due to complications. If detected incidentally during cardiac or thoracic surgery, the best may be to leave it alone.