A synthetic quartz glass lid is provided comprising a synthetic quartz glass and an adhesive formed on a periphery of a main surface of the window member. Further, an optical device package is provided comprising a box-shaped receptacle having an open upper end, an optical device received in the receptacle, and a window member of synthetic quartz glass bonded to the upper end of the receptacle with an adhesive. The adhesive is a low-melting metallic glass consisting of Te, Ag and at least one element selected from W, V, P, Ba, and Zr.