Abstract: A method for manufacturing a light-emitting-element mounting substrate includes a step of applying a glass paste using powder of a glass material having a softening point higher than a softening point of a glass component contained in a glass-ceramic green sheet and lower than a melting point of silver so as to cover a conductor paste which is applied to a main surface of the glass-ceramic green sheet and consists of or consists primarily of silver; and a step of coating a metal layer obtained by heating them and sintering the conductor paste, with a transparent glass layer obtained by melting and then cooling the glass paste. By using the glass paste, the reaction of silver in the conductor paste with the glass component in the glass paste upon heating is suppressed, and the metal layer can be coated with the glass layer having high transparency.