Information Network has been grown up and spread out to the entire globe extremely swiftly in recent years. It has also very quickly turned out to be a world-wide new infrastructure of the society and made great influence to the ways people work, live, learn and think.The astonished phenomenon has been regarded as a real frontier and focus in science and engineering, extracting great attentions from science and engineering circle as well as the whole world.

An attempt is made in the paper to establish a new discipline, the information network engineering, based on the above phenomenon.First, the concept of information network is re-defined clearly here and then the working mechanism of information network is analyzed in depth. A comparative discussion on the functions embodied in human activities and that performed in information network is carried out and the working relationship between man and information network is found to be the socalled symbiosis. As a result of the analyses above, a list of the important issues and directions in information network engineering study is briefly summarized.