A novel light-emitting device that is highly convenient, useful, or reliable is provided. The light-emitting device includes a first electrode, a second electrode, a unit, and a first layer. The unit is positioned between the first electrode and the second electrode and includes a second layer, a third layer, and a fourth layer. The second layer is positioned between the third layer and the fourth layer and contains a light-emitting material. The third layer is positioned between the second layer and the second electrode, is in contact with the second layer, and contains a first material, and an organometallic complex of an alkali metal or an organometallic complex of an alkaline earth metal. The fourth layer is positioned between the first electrode and the second layer and contains a second material. The first layer is positioned between the first electrode and the unit and contains a second material and a material having an electron acceptor property. The second material has a first refractive index. The first refractive index is higher than or equal to 1.5 and lower than or equal to 1.75 in a wavelength range of 455 nm to 465 nm inclusive. The second material has a HOMO level. The HOMO level is higher than or equal to −5.7 eV and lower than or equal to −5.3 eV.