In pervasive computing environment, applications available for end-users are abundant, distributed and heterogeneous. In order to share these applications, this paper presents a user-centric applications sharing model which called U-ASM. The basic concepts and structure of U-ASM are defined, which abstract the applications from service providers as well as end-users. The paper uses ontology to organize distributed applications as a logic unit with semantic relationships and utilizes virtualization technology to encapsulate applications. Finally the paper presents a prototype of the U-ASM which validates feasibility and validity of the model. The research result has been applied in R&D infrastructure and facility development of ministry of science and technology and has great flexibility and extensibility.