Abstract: After the persistent practice in the 1990’s, using open system idea to integrate large scale computer systems has been the consentient fact In order to embody high efficiency and intelligent collaboration in open systems, core architecture, called common agent request broker architecture （CARBA）, is established based on mobile agent, and agent based computing basic architecture （ABCBA） is constructed based on CARBA Structure of CARBA and ABCBA, domain interface of ABCBA, extension of ABCBA in nomadic environment, and relation among ABCBA OMA, and ODP are discussed in detail Experiment results are given, which show that it is feasible to use ABCBA to improve efficiency and collaboration in open systems and ABCBA is suitable in both wired and wireless network environment