The complexity of coal rock fracture has a significant influence on the fracture flow conductivity. Accurate assessment of the true diversion capability of the complex fracture of coal rock can provide technical support for the design and construction of the field fracturing program through the long term diversion test. In this paper, the experimental evaluation of the long term flow conductivity of the horizontal fracture of coal rock and the T type fracture are carried out, the results of which prove that when paved-sand content is same, coal and rock fracture conductivity is influenced by fracture complexity significantly, the more complexity, the greater total crack sanding, the stronger coal rock fracture flow capacity; also under the action of closing pressure, support agent compaction is more obvious; Under the same closing pressure, with the increase of compaction duration, the fracture conductivity of coal rock decreased gradually, and with the increase of the complexity of the coal and rock fracture, the decline range increased gradually. In this paper, the experimental results well explain the influence of different test conditions of coal and rock fracture complexity on fracture flow capacity and is an improvement for the existing research and evaluation of coal rock fracture conductivity, and is of guiding significance for CBM well fracture parameter optimization in the future.