The mouse heterotopic fully vascularized cardiac transplantation model has come into widespread use. However, the technique is still difficult. Therefore, simple anastomosis was introduced. The donor ascending aorta was sutured end-to-side to the recipient abdominal aorta and the donor pulmonary artery was anastomosed to the recipient inferior vena cava. The main point was only 4 stitches on 1 side between proximal and distal anastomosis of the recipient aorta and inferior vena cava. When beginners tried to perform the same procedure, they were able to complete the first successful procedure after 11 trials and achieved 90% success after 78 operations. The simple anastomosis is safe and shortens the operation time.