Abstract: A neon light control device has a control box and at least one voltage transformer, wherein the control box has multiple outlet ports and the voltage transformer has an inlet port and an outlet port. The voltage transformer is detachably connected to the control box by a wire between one of the outlet ports and one of the inlet ports. When either the control box or the voltage transformer has a breakdown, only the damaged element needs to be repaired or replaced. Thus the replacement of the entire control device is not necessary.