A wavelength conversion member includes: a heat conducting layer; a sapphire substrate having a third surface directly contact with a second surface of the heat conducting layer and the fourth surface opposite to the third surface; and a phosphor layer having a fifth surface directly contact with the fourth surface and a sixth surface opposite to the fifth surface, the phosphor layer including phosphor. At least one of an area of a first surface and an area of the second surface of the heat conducting layer is at least 2800 times as large as an area of the sixth surface of the phosphor layer. At least one of an area of the third surface and an area of the fourth surface of the sapphire substrate is at least two times as large as the area of the sixth surface of the phosphor layer.