He, P. Deng, B. Guo, D.Z. Li, Q. Liu, B.Q. Ma, Y. Wang, X.J. Yang, Y.C. Zhang, L. JACoW Publishing Geneva, Switzerland 978-3-95450-206-6 10.18429/JACoW-FLS2018-TUP2WD04 English 52-55 TUP2WD04 ion vacuum storage-ring radiation photon Contribution to a conference proceedings 2018 2018-06 https://doi.org/10.18429/JACoW-FLS2018-TUP2WD04 http://jacow.org/fls2018/papers/tup2wd04.pdf In the design process of HEPS vacuum system, we meet the following limitations. Vacuum chamber must fit inside multipole magnet bore diameter of 25mm (without touching). Water channels and x-ray extraction ports must pass through a 11mm vertical pole gap. Provide an average pressure of 1nTorr during operations with 200mA beam current. Control thermal drift of BPM to ~μm and vibration amplitude ~nm level. Minimize impedance effects. This paper introduces the design of various vacuum chambers, including material selection, mechanical simulation analysis, welding test and so on.