Based on the detailed analysis of the process of modern aITcraft mamtenance , this paper presents the concept , purposes , principle andstructure of integrated mamtenance information system(IMIS) , and summanses the major researches and projects m support of developing the system. IMIS is capable of processmg and íntegratmg ínformatlOn from several air force data bases to provide technical support to mamtenance technicians. Through a portable mamtenance aids , IMIS provides instructlOns for accomplíshíng mamtenance tasks. Thís paper glves a comprehenslve description of the concept, theory and methods as a kind of integrated mamtenance information delivery.