An assembling structure of an electronic component includes an electronic component including a component main body having a plurality of lead terminals protruding from side surfaces of the component main body, and a housing member in which the electronic component is inserted and accommodated and which holds a plurality of terminal fittings connected to the lead terminals. Each lead terminal includes a base end protruding from at least one side surface of the component main body and a connecting portion which is connected to the base end and which droops along the side surface, and the plurality of lead terminals are provided to be protruded from at least one side surface of the component main body in the width direction of the side surface. The side surface of the component main body is provided with an insulating member.