A method of manufacturing packages having contents sealed therein, including: a step of forming cavities in a plurality of package forming areas on a first wafer; a step of bonding the first wafer and a second wafer while arranging the contents in the cavities; and a step of irradiating a bonded wafer member with a laser and separating the packages into pieces, characterized in that dummy cavities are formed on an outside of the package forming area in an outermost periphery of the first wafer in the cavity forming step.