Bian, T.J. Cui, X. Gao, J. Zhang, C. JACoW Geneva, Switzerland 978-3-95450-182-3 10.18429/JACoW-IPAC2017-WEPIK022 English 2968-2970 WEPIK022 Contribution to a conference proceedings 2017 2017-05 http://dx.doi.org/10.18429/JACoW-IPAC2017-WEPIK022 http://jacow.org/ipac2017/papers/wepik022.pdf In September 2012, Chinese scientists proposed a Circular Electron Positron Collider(CEPC) at 240 GeV centre of mass for Higgs studies. The CEPC booster(CEPCB) provides 120 GeV electron and positron beams to the CEPC collider for top-up injection. We foucus on the beam dynamic study for CEPCB and analyse the key point of CEPCB lattice design. In this paper, a lattice design with good dynamic aperture is proposed.