(Problem to be Solved)To provide a wavelength converting device which can efficiently exhaust heat from the wavelength converting member using a heat dissipating member.(Solution)The wavelength converting device includes a heat dissipating member, a wavelength converting member disposed on the heat dissipating member, and a connecting member which connects the heat dissipating member and the wavelength converting member. Particularly, the wavelength converting member includes an upper surface, side surfaces, and a lower surface, and the connecting member is thermally connected to the side surfaces and the lower surface of the wavelength converting member.