[Problem]We provide wavelength conversion members with greater intensity of output light. Solution means : A wavelength conversion member comprising a wavelength conversion layer having a support and a phosphor layer comprising a phosphor disposed on the support and whose composition is represented by equation (1) below. The wavelength conversion member has a thickness of 5 μm to 155 μm or less of the phosphor layer, and in a cross section perc ratio percrituated to the arrangement surface of the wavelength conversion layer to the support, the ratio of the sum of the particle cross-sectional area of the phosphor is 5% to less than 40% with respect to the cross-sectional area of the wavelength conversion layer. In the following formula (1), M1 indicates at least one selected from rare earth elements other than La and Ce, and the total molar content of Y, Gd and Lu in M1 is 90% or more, and p, q, r, and s are 2. 7≦p＋q＋r≦3． 3、0≦r≦1． 2, 10 ≦≦12, and 0
