The invention relates to an isotope composition, a material containing the isotope composition and used for preparing an organic electroluminescent device, the organic electroluminescent device, and electronic equipment. The isotope composition at least contains a mixture of a first compound and a second compound; the first compound and the second compound are both organic compounds and have the same chemical structure; the first compound contains one or more types of low-abundance stable isotope atoms, and the mass content of the first compound in the mixture is 2%-99%; and the second compound does not contain the low-abundance stable isotope atoms. According to the isotope composition, the life of the organic electroluminescent device can be effectively prolonged, and the higher component efficiency can be effectively achieved.