A bialkali antimonide photocathode is of high quantum efficiency(QE) for visible lights

low emittance

and relatively long life time in the strong RF field and practical vacuum.It produces high-brightness electron beams to meet the energy recovery need of a linac.This kind of photocathode contains cesium

hence the need of preparing

transferring and operating it in ultra high vacuum(UHV).In this paper

we report the design of a bialkali antimonide photocathode preparation apparatus developed at SINAP.Functions of the equipment are described.The UHV pumping

the photocathode substrate cleaning and preparation the K-Cs-Sb photocathode are presented in detail.The QE is measured under different laser power densities and wavelengths.Other testing experiments for performance of the K-Cs-Sb photocathode prepared with this apparatus are conceived.