Accelerator Physics Issues in the Bepcii

The Beijing Electron-Positron Collider (BEPC) has been running for both high energy physics (HEP) and synchrotron radiation (SR) researches since 1989. Good performance of BEPC accomplishes a lot of achievements in the tau-charm region over the past decade, and in many fields of SR applications as well. As an upgrading scheme from BEPC, the BEPCII project was approved by the Chinese government in the early time of this year, with a micro-beta scheme and multi-bunch collision in a doublering machine installed in the current BEPC tunnel. The design work of the BEPCII is being carried on. This paper will describe the main progresses on the design of the BEPCII in the field of accelerator physics.