As the major upgrade of the BEPC (Beijing Electron Positron Collider), BEPC-II aims on working at the tau-charm energy with a double ring e+-e− factory-like collider, and providing partially dedicated synchrotron radiation (SR) light to users as well. As a collider, the commissioning of the BEPC-II started from Nov. 2006, and got to the luminosity of 3×1032cm-2s-1 at 1.89 GeV in May 2009. A lot of accelerator physics problems, such as optics realization, impedance problem, detector background, beam lifetimie, luminosity optimization, etc., are met during the commissioning of the storage rings. As a light source, the SR ring of the BEPC-II was also commissioned and delivered beams to users at 2.5 GeV and 250 mA for more than 5 months during the year of 2007 to 2009. Some future plans for higher luminosity are proposed and being studied. In this talk, the main design work of the BEPC-II storage rings, accelerator physics issues in the luminosity commissioning and performance for HEP and SR users, and possible future proposals, are discussed in detail.