A light emitting substrate comprising: a phosphor substrate ; and at least one light emitting element mounted on a front face of the phosphor substrate and being formed as a chip sized package, CSP, and comprising a light emitting diode, LED covered with a phosphor sealing layer comprising a first phosphor, the phosphor substrate comprising: an insulating substrate ; an electrode layer disposed on a front face of the insulating substrate comprising a bonded portion bonded to the light emitting element ; and a phosphor layer which is disposed on the front face of the insulating substrate to form the front face of the phosphor substrate and includes a second phosphor in which a light emission peak wavelength, in a case where light emitted by the light emitting element is used as excitation light, is in a visible light region, wherein a surface (34A1, 34B1) of the electrode layer facing an outer side in a thickness direction of the insulating substrate is a flat surface, and at least a part of the phosphor layer is disposed on the front surface of the electrode layer other than and around the bonded portion bonded to the light emitting element , and the region of the front face of the insulating substrate where the phosphor layer is disposed is a region that is equal to or more than 80% of the front face of the insulating substrate . a phosphor substrate ; and at least one light emitting element mounted on a front face of the phosphor substrate and being formed as a chip sized package, CSP, and comprising a light emitting diode, LED covered with a phosphor sealing layer comprising a first phosphor, the phosphor substrate comprising: an insulating substrate ; an electrode layer disposed on a front face of the insulating substrate comprising a bonded portion bonded to the light emitting element ; and a phosphor layer which is disposed on the front face of the insulating substrate to form the front face of the phosphor substrate and includes a second phosphor in which a light emission peak wavelength, in a case where light emitted by the light emitting element is used as excitation light, is in a visible light region, wherein a surface (34A1, 34B1) of the electrode layer facing an outer side in a thickness direction of the insulating substrate is a flat surface, and at least a part of the phosphor layer is disposed on the front surface of the electrode layer other than and around the bonded portion bonded to the light emitting element , and the region of the front face of the insulating substrate where the phosphor layer is disposed is a region that is equal to or more than 80% of the front face of the insulating substrate . an insulating substrate ; an electrode layer disposed on a front face of the insulating substrate comprising a bonded portion bonded to the light emitting element ; and a phosphor layer which is disposed on the front face of the insulating substrate to form the front face of the phosphor substrate and includes a second phosphor in which a light emission peak wavelength, in a case where light emitted by the light emitting element is used as excitation light, is in a visible light region, wherein a surface (34A1, 34B1) of the electrode layer facing an outer side in a thickness direction of the insulating substrate is a flat surface, and at least a part of the phosphor layer is disposed on the front surface of the electrode layer other than and around the bonded portion bonded to the light emitting element , and the region of the front face of the insulating substrate where the phosphor layer is disposed is a region that is equal to or more than 80% of the front face of the insulating substrate . <EOS>