The utility model provides a fixed layer intermittent mixing gas making device. Inlets of upper coal gas recovery pipelines of a gas making furnace are inserted in a dry distillation layer inside a hearth; and pipeline wall cracks are arranged on the upper coal gas recovery pipelines and communicated with a blast pipeline at the bottom of the gas making furnace through a secondary air supplementary valve. A plurality of upper coal gas recovery pipelines are arranged on the gas making furnace. Secondary air can be supplemented for the dry distillation layer inside the hearth during the blowing stage; the partial afterheat of fume is also recovered while the pipelines are safely protected, and the thickness of the dry distillation layer is increased under the situation of maintaining the thickness of a normal gasifying layer, so that more heat is stored for blowing gas. The inlets of the coal gas recovery pipelines are inserted in the dry distillation layer inside the hearth, which is considered from angles of smooth transition of upper coal gas transmission and upper coal gas recovery; and when upper coal gas is recovered, the system resistance can not be increased.