This paper introduced Professor Jiang Zhiyan’s clinical experience in the treatment of Mycoplasma pneumoniae in children by collateral-unblocking therapy. Professor Jiang advocated that the mild cases in acute stage were treated by lung-clearing and collateral-unblocking therapy, the severe cases in acute stage were treated by phlegm-removing and collateral-unblocking therapy, and the cases in the recovery stage were treated by deficiency-tonifying and collateral-unblocking therapy. One proven case was presented for example.