Based on the com b inat ion of o rgan izat ion theo ry and m u lt i2in telligen t agen t techno logy, a new app roach of comp lex info rm at ion system developm en t is p ropo sed in th is paper. F irst ly, a comp lex info rm at ion system is taken as a m u lt i2agen t system , the characterist ics of the system is analyzed, and a model ofm u lt i2agen t o rgan izat ion is bu ilt to describe them acro2st ructu re of the system and to def ine the funct ion dem ands. Secondly,w ith the rest rict ion of the techno logy and resou rces,w e determ ine the o rgan izat ion funct ion s fo r differen t agen t s and their respon sib ilit ies acco rdingly. Th irdly, based on the o rgan izat ion model,w e design the concep tualmodels fo r each agen t by "belief2desire2in ten t ion" (BD I) st ructu re. These models serve as the operat ive developm en t app roaches to realize the info rm at ion sys2 tem on compu ter. F inally,w e develop a p ro tocal system on a cooperat ion wo rk ing p latfo rm (MBO S) based on the concep tualmodels.