The car-wash wastewater has proportion of Turbidity, COD and Oil that exceeds the minimum standard quality and can cause considerable impacts to polute the environment if they are not processed in well manner. The wastewater treatment with ultrafiltration membrane technology has been selected for this reasearch due to the advantages embeded along with it. Furthermore, this research has been conducted to analyze the effects of pore (PES Membrane (Poly Ether Sulfone) 10 Da and PS (Polysulfone) 25 kDa) on certain pressure (1,2,3 Bar) to calculate the performance of membrane that being stated with flux and the membran ability to reduce the proportion of turbidity, COD and oil in wastewater. Based on this research, all variations show unsignificant differences in the parameters, and the result from those variations meet the standard quality for domestic waste which aligned with Central Java Regional Law No. 5/2012. The most optimum condition is processing the wastewater with Membrane PS25 at 1 Bar pressure, by reason this variation has a larger pore than a membrane PES10. As a result, it has higher value of flux and requires small amount of energy because it is operated at low pressure, thus it makes the cost is in low-level. The rejection on membrane PS25 with 1 Bar pressure is 93,37% (Turbidity), 78,69% (COD) and 84,62% (Oil).