Disclosed is a surface acoustic wave device wherein an encapsulation resin for sealing a mounting board and a surface acoustic wave element has a three-layer structure. The resin forming the intermediate layer has a higher elastic modulus than the resin forming the outermost layer, and the resin forming the innermost layer has a lower elastic modulus than the resin forming the outermost layer. Byhaving such an encapsulation resin of three-layer structure, deformation of a bump when an external force is applied to the surface acoustic wave device is reduced, and stress applied to a bump due to temperature change is also reduced.