Functional element units and a connection line electrically connecting the functional element units are formed on one principal surface of a piezoelectric motherboard. A resin support layer enclosing the functional element units is formed on the one principal surface of the motherboard. An elastic wave device with the functional units is obtained by dividing a multilayer body including the motherboard, the functional element units, and the support layer into a plurality of sections along a dicing line. The connection line includes a line main body positioned on the dicing line, and a connection unit in which the line main body and the functional element units are electrically connected. Prior to dividing the multilayer body, a retaining member made of resin which straddles the line main body in the width direction of the line main body is formed separate from the support layer on the motherboard.