A method of manufacturing joined body including: firstly, putting sheet material in intimate contact with first substrate to cover, with resin layer of sheet material, areas of first substrate including first area, boundary area surrounding first area, and second area located across from first area with respect to boundary area, sheet material being laminate including resin layer and separable layer, resin layer containing uncured sealing resin; secondly, curing sealing resin in part of resin layer covering boundary area; thirdly, removing, along with separable layer, part of resin layer covering second area in one direction from one end towards the other of two ends of second area; and fourthly, joining first substrate and second substrate together by arranging second substrate to face first substrate and curing sealing resin with parts of resin layer covering boundary area and first area located between second substrate and first substrate.