Objective: We report a rare, rapid, huge formation of the left ventricular pseudoaneurysm after sutureless repair with GRF glue. Methods: The case was a 70-year-old male, who received an emergency operation for a subacute left ventricular free wall rupture (LVFWR) complicated by acute myocardial infarction. At that time the left ventricle was wrapped with equine pericardium by using gelatin resorcin formaldehyde (GRF) glue (sutureless repair). The patient had been stable for 13 months but suffered acute heart failure. The left ventricular angiogram (LVG) revealed a huge left ventricular aneurysm and 75% stenosis in the middle segment of the left anterior descending artery (LAD). He had received the LVG one month before. There was a small concavity in the inferior wall of the left ventricle. A huge pseudoaneurysm had formed within one month. Results: A left ventricle direct patch closure, and coronary artery bypass were performed. In the pathological findings, the wall of the aneurysm was almost elastic collagen tissue. Conclusions: Sutureless repair is an effective technique for subacute left ventricular free wall rupture, a left ventricular pseudoaneurysm has to be cared for the late period.