A method for producing a multilayer substrate includes stacking a first substrate, the first substrate having a circuit pattern; stacking a connector, the connector coupling onto said first substrate, the connector having a ring structure, the ring structure having a plurality of holes separated a predetermined distance from one another; and stacking a second substrate, the second substrate coupling onto said first substrate by inserting said connector, the second substrate having a circuit pattern, the circuit pattern being electrically connected to a circuit pattern formed on said first substrate, the circuit pattern being electrically connected using the plurality of holes formed on said connector. The method of producing a multilayer substrate can shield the EMI generated by a high-speed switching element.