Abstract: In this paper, the aspects of accuracy, reliability and sensitivity of an engineering control network are systematically disscussed. It is proposed that a monitoring network should take the sensitivity as the pricipal quality criterion in network design.With a specified deformation model, a computer aided monitoring network design system (CAMNDS) concerning the quality criteria of sensitivty, reliability and economy is developed. In the system, the main judgement for modifying the design is the sensitive elements. Therefore it has both analytic nature and computer aided simulation nature. The system can also be used in the design of general engineering control network. Finally a typical example is given using the system and some useful conclusion are drawn.