White a.c. electroluminescent phosphors and display devices were made in ZnS which were activated by Mn and Cu with difference concentration.Three emission peaks were observed at 450 nm,520 nm and 585 nm respectively.Emission spectrum was changed with the concentration of Mn and Cu.White phosphors were obtained with suitable concentration of Mn and Cu.It was showed that the phosphor center of Mn is sensitized by the one of Cu at low voltage and is excitaed by impact each other at high voltage.Therefore,the white a.c. ZnS:Mn,Cu electroluminescent display devices can be obtained by the different exciting mechanism of two phosphor center.