Effects of size of secondary phase particles on recrystallized structure in 3003 hot rolled aluminum foil were investigated by OM（optical microscope） and SEM（scanning electron microscope） and TEM（transmission electron microscope） at different annealed temperature and holding time.It is found that recrystallized grain size in the 3003 aluminum foil is decreased with increasing in annealed temperature.At a given annealed temperature,the recrytsallized grain size is nearly independent of the holding time when it is below 16 hours.An explanation was presented with the help of secondary phase size from the mechanism of particle stimulated nucleation,and it also provided a way to refine recrystallized structure.