The utility model discloses a combined gunpowder delay mechanism suitable for detonation products in gun perforation operation of oil and gas well, comprising an ignition cap, a plurality of delay explosive columns and output caps orderly sheathed in a delay pipe casing, and the ignition cap is connected with the delay pipe casing at one end of the ignition cap through an ignition cap base. Each delay pipe casing is provided with uniformly distributed venting holes and a plurality of delay explosive columns of identical pressing process, powder ingredient, shape and specification. The utility model is characterized in that the pressing process and the charging process of the delay pipe is separated, adopting level pressing process, lightening the labor intensity of manufacturing people, and improving the security of pressing; furthermore, the number of the delay explosive columns can be assembled freely according to different delay requirements of detonation products to form delay line products with different delay time. The utility model has remarkable advantages that it is especially adapted for volume-producing with low cost, wide range of delay time, high delaying precision, stable performance, and good reliability.