Prenatal aortic valvuloplasty is performed only in few perinatal centers in the world. Critical aortic stenosis which can lead to hypoplastic left heart syndrome or severe fetal heart failure with nonimmune hydrops is an indication for this procedure. Prenatal intervention can change the natural course of the disease. Authors present the first successful fetal balloon aortic valvuloplasty in Poland. It was performed in a 29-week fetus with critical aortic stenosis, severe impairment of left ventricular function, heart failure and fetal hydrops. After successful intervention, without any complications, left ventricular function and fetal condition improved gradually Effective fetal intervention was possible after few months of preparation and building a team of specialists. This is the first successful fetal cardiac intervention in Poland, which opens the way to the new era of fetal cardiology and hopefully will lead to improve results in children with this critical heart defect.