Introduction: primary cardiac tumors are those having their origin in the myocardium or pericardium. The 90% are benign, not invasive, but due to their location they can cause severe hemodynamic alterations and arrhythmias. Case report: two patients, carriers of cardiac tumors that were diagnosed in prenatal stages, a 32 year-old pregnant woman, carrier of a Neurofibromatosis, in the fetal echography of her child, two types of cardiac tumors were identified: an atrial myxoma and a fibroma, along with a fetus who presented a rhabdomyoma that was diagnosed during the prenatal stage and confirmed at birth having a spontaneous remission. Conclusions: more frequently fetal echocardiography makes possible the intrauterine diagnosis of cardiac tumors. Rhabdomyomas have a spontaneous remission in more than 50% of the cases, but they can be a marker of Tuberous Sclerosis. Cardiac tumors are associated with other congenital affections and require surgical treatment. All these aspects must be considered to accomplish genetic counseling to the family.