WAVELENGTH CONVERSION MATERIAL

Provided is a wavelength conversion member that can improve the color balance of emitted light. A wavelength conversion member 1 includes a phosphor 2 encapsulated within a glass tube 10, wherein the glass tube 10 includes: a first flat-plate portion 11 and a second flat-plate portion 12 opposed to each other in a first direction (z direction) perpendicular to a longitudinal direction (y direction) of the glass tube 10; and a third flat-plate portion 13 and a fourth flat-plate portion 14 opposed to each other in a second direction (x direction) perpendicular to both the longitudinal direction (y direction) of the glass tube 10 and the first direction (z direction), the first flat-plate portion 11 is located on a light incident side of the glass tube 10 through which excitation light 3 for exciting the phosphor 2 enters the glass tube 10, the second flat-plate portion 12 is located on a light exit side of the glass tube 10 through which fluorescence 4 from the phosphor 2 is emitted from the glass tube 10, at least one of a first corner 21 connecting between the first flat-plate portion 11 and the third flat-plate portion 13 and a second corner 22 connecting between the first flat-plate portion 11 and the fourth flat-plate portion 14 is chamfered.