As innovative technologies like ubiquitous computing and grid computing continue to emerge and become more popular, the amount of resource available on them has come to an extreme extend. However, traditional provider-centric resource sharing architecture focuses on defining service interfaces so that users must know exactly where and how to explicitly ask for resources. This method can not satisfy user?s personalized task requirements. To solve the problem, this paper puts forward a usercentric resource sharing architecture which called URSA. The U-RSA mainly focuses on abstracting the currently personal computing environment from user?s perspective. This paper also discusses the key technologies of our architecture.