Sequencing batch reactor (SBR) is a time-oriented wastewater treatment (WWT) system in a single reactor with flow and energy input according to the predetermined operational cycle time. The treatment efficiency of SBR varies with the duration of the cycle time, which affects the reactor size and hence the cost of WWT plant. This paper presents an experimental study in a bench scale SBR model with a working volume of 15 L with an onjective to determine the optimum cycle time for simultaneous removal of carbon and nutrient from the dairy wastewater. Using the equalized dairy wastewater experiments with four cycle times of 8 h, 6 h, 4 h and 2 h were conducted and the effluent concentrations were compared to the effluent standards. In conclusion, the data suggest the SBR process with 6 h cycle time as the optimum cycle time for treating dairy wastewater for simultaneous carbon and nutrient removal.