In order to explore the activator migration through porous media in MEOR process，the flooding experiments of different major activators in filled sand cores and crude oil saturated cores were performed. In addition，the migration of activator with different injection rate and concentration in the cores were also investigated. Results showed that clogging of the cores is the lowest with glucose compared with corn slurry and starch solution. For the low price and good activation effect，corn slurry was studied further，the suitable injection conditions of which were found to be 10 g·L-1 of concentration and 1.2 ml·min-1 of injection rate. The activator migration in crude oil saturated cores is more smooth than that in filled sand cores.