The invention relates to a mould, manufacturing process and installation method of a small gate stack. The mould of the small gate stack comprises bottom moulds, side moulds and clamping plates. Pairsof side moulds are vertically installed on the front and rear sides of the bottom moulds, the left and right ends of the side moulds are correspondingly provided with the clamping plates through split bolts, a plurality of partition plates arranged vertically and in parallel are installed on the opposite inner sides of the side moulds, and the side moulds are divided into a plurality of gate stack cavities through the partition plates. A pair of fixing plates are installed on the top of the partition plates at intervals in the transverse direction, the left and right ends of the fixing platesare correspondingly connected with the clamping plates in an overlapped mode, two or more than two fastening bolts are connected between the fixing plates in the middle of each gate stack cavity andthe bottom moulds in a pulling mode, and each fastening bolt is provided with a PVC sleeve in a penetrating mode. According to the mould of the small gate stack, a plurality of gate stacks can be manufactured at one time, and each gate stack is prefabricated with installation holes connected with a wall, thus installation of the gate stacks is fast and firm; and conical holes are reserved on one end faces of the gate stacks, mortar is used for sealing after the gate stacks and the wall are installed, the overall structure is beautiful, and operation is easy.