Three types of Yb 3+ optical centers of ions have been found in YScO3. The first one is a highly symmetric optical center with a local symmetry C3i(Y 3+ ) and a lifetime of τ I 77K = 4.0 ms, which is formed as a result of substitution of Y 3+ ions for ytterbium ions in the crystal lattice. The second center has local symmetry C2 II (Y 3+ ) and a lifetime of τ77K II = 1.0 ms. The third one is a low-symmetry C2 II (Sc 3+ ) center with lifetimes of τ77K II = 0.620 ms.