Nowadays, the primary energy supply is based on the fossil energy resource, a worldwide energy demanding of construction and sharply increasing environment pollution are impelling us looking for cleaner resource. In this context, it is pointed to the possibility for solar roof using on the dwelling house. On-site solar roof can produce clean electricity for residents, and protect the sun heating the indoor air directly by reflecting and absorbing sunlight. In this thesis, also the environment impact is described to interpret the benefits of solar roof. In Japan, almost 20 years’ experiences for developing and popularizing solar roof could provide China many guides and advice. Therefore, an analysis on Japanese solar roof fixing on dwelling is carried out to evaluate the energy efficiency and carbon emission reduction by CASBEE , furthermore, a life-cycle cost of that will also be calculated by LCC .