The statistical relations between the arrival time, maximum time of proton events and the flare-associated longitudinal position are studied in detail by using data of solar flares and proton events from 1966 through 1992. It is concluded that the above two time processes are the shortest when solar flares are at longitudinal positions which are the footpoints of the large-scale interplanetary magnet field lines connecting with the earth. The result supports the two-stage diffusion model, which asserts that the solar flare protons propagate in the interplanetary space following the coronal transport.