Abstract: This article analyzes the relationship of regulating position and airflow stability of the underground complex ventilation system. According to the characteristics that there are lots of diagonal branches in the complex ventilation network, the fast regulation and optimization technology of mine ventilation system in production mine is put forward based on the diagonal classification recognition technology of undirected graph and air quantity sensitivity analysis method. Firstly, the diagonal classification recognition technology is used for the actual complex ventilation system. Secondly, using the increasing resistance or the decreasing resistance regulation type, the regulation branch is determined by searching the branches of the positive and negative traverse in the current level diagonal structure which has already installed the regulation devices and has the bigger air quantity sensibility degree. Lastly, the regulation quantity of the regulation branch is revealed by the air quantity sensibility degree. Under the premise that without changing the existing ventilation regulation devices as far as possible, and keeping that the air quantity of roadway satisfies the required airflow requirements, it is easy to realize the fast regulation of airflow distribution of mine ventilation system in production mine.