In enhanced oil recovery (EOR), nanoparticles have gained the potential to improve foam stability. In this study, the potential of fly ash to produce stable foam by using shaker was studied. Fly ash nanoparticles were developed by the mechanical treatment using ball mill. Sample to ball ratio of 1 to 10 was applied to investigate the effect of ball milling on particle size distribution of fly ash. The mechanically activated fly ash was mixed at various concentrations (ppm) with the anionic foaming surfactants AOS14-16. Foam stability tests were performed at ambient conditions by making solution through shaker. Stable foams were generated using varies types of fly ash particles. It was observed that the small sized fly ash has more potential towards foam forming ability and foam stability. Therefore, the mechanically activated fly ash resulted in a considerably increased EOR. © 2016 Penerbit UTM Press. All rights reserved.