We have investigated the effects of doping concentration in polysilicon floating gate on the endurance characteristics of the EEPROM cell haying the structure of spacer select transistor. Several samples were prepared with different implantation conditions of phosphorus for the floating gate. Results show the dependence of doping concentration in polysilicon floating gate on performance of EEPROM cell from the floating gate engineering point of view. All of the samples were endured up to half million programming/erasing cycle. However, the best $program-{Delta}V_{T}$ characteristic was obtained in the cell doped at the dose of $1{ imes}10^{15}/cm^{2}$.