Abstract: The method of mearsurement and study on secondary electron emission coefficient by electrons produced by electron gun limits the application with complicated implementation process and difficult acquisition of micro-flow incident primary electrons. Therefore an acurate measurement of secondary electron emission coefficient needs the method of obtaining incident primary electeonics by ultraviolet excitation metal zinc through high voltage power supply and electrometer. Respectively test stand-alone dynode with secondary electron emission coefficient and multiplier gain in electron multiplier. An acurate measurement of secondary electron emission coefficient is obtained. Study the secondary electron emission performance of magnesium oxide（MgO）material after comparison. Hence the electron multiplier gain based on magnesium oxide emission materials are acquired.