The invention relates to a stable code scanning cashier device which comprises a shell and a scanner, the shell is in a cuboid shape, the scanner is arranged in the shell, a connecting mechanism and a heat dissipation mechanism are arranged on the shell, and the connecting mechanism comprises a moving pipe, a glass plate and two connecting assemblies. Each connecting assembly comprises a connecting pipe, a moving disc and a connecting unit, the heat dissipation mechanism comprises a rotating shaft, two bearings and two heat dissipation assemblies, each heat dissipation assembly comprises an air pipe, a filter screen, fan blades, an air hole and a transmission unit, the air holes are formed in the shell, the air pipes and the rotating shaft are coaxially arranged, the air pipes penetrate through the air holes, and the air pipes are in sealed connection with the inner wall of the air holes. According to the stable code scanning cashier device, the code scanning stability is improved through the connecting mechanism, a mobile phone is prevented from shaking in the code scanning process, and in addition, the heat dissipation function is achieved through the heat dissipation mechanism.