The authors developed a new waterproof-packed infusion device for easy and sterile in-storage hypothermic perfusion during organ transportation for heart and lung transplantation. They examined the accessibility and efficacy of this infusion device for portable heart and lung preservation in canine transplant models. Sixteen heart and bilateral lung blocks were preserved by an in-storage hypothermic perfusion technique using the infusion device with University of Wisconsin solution. Of 16 dog recipients, 5 underwent orthotopic heart transplantation with cardiopulmonary bypass, and 5 dogs received left lung transplantation; the remaining heart and lung blocks were intrathoracically transplanted into 6 dogs. Functional status and histology of 11 heart and 11 lung allografts were evaluated by post-transplant course, hemodynamic parameters, arterial blood gas measurements, microscopic examination, and so on. Eleven transplanted hearts showed good cardiac performance and maintained systemic circulation after weaning from cardiopulmonary bypass. Eleven transplanted lungs had excellent respiratory function, and all five dogs with left lung transplantation survived for 5-46 days (mean: 18.8 days). These results suggest that in-storage hypothermic perfusion with this waterproof-packed infusion device can be a useful technique for long-term organ preservation in heart and lung transplantation.