There are many galleries with different functions and design requirements in nuclear power plant (NPP), which are set for linking the pipes and cables between the workshops and providing the accesses for personnel, but there is not specific gallery design code for the 3rd Generation NPP in China at present. Combined with the gallery design in Taishan Europe pressure-water reactor (EPR) NPP, the characteristic, basic functions and main design contents of galleries were described in detail, and the method and design idea of the gallery were proposed for EPR NPP. This paper suggests some optimization approaches for gallery engineering design, which will provide references for the follow-up NPP and promote the establishment of design code.