Abstract : This thesis describes the interest of using microprogrammable microprocessors for on-line triggering and event filtering i n high energy physics experiments. The first part is used to analyse this problem and to show the principal difficulties . The second part describes Our solution, which consist of adding in the initial informatic structure a great transfert and treatment capability by a multiprocessor architecture, suitable to each experiment. The third part is dedicated to the description of Our fast processor GESPRO and of its software tools specially written for this realization. Performances obtained are then given. The last part is used to detail the results obtained since 1975 on two experiments (NA2 and NA10) on the SPS of CERN at Geneva.