Different amounts of CuO are used to synthesize CaCuTi O (CCTO, -1 ≤ x ≤ 1) powders in this work. In order to investigate the effects of Cu constituent on the componential, morphological, and dielectric properties, 975 C is selected as the sintering temperature to prepare the ceramic pellets with different x values from -0.2 to 0.2. They basically keep the same component and morphology despite the different Cu constituents in the ceramics. Cu component has complex effects on their dielectric properties, whose changes are not linear with the Cu increase. However, the CCTO ceramic sample has the most frequency- independent dielectric constant and the lowest dielectric loss. © 2013 Elsevier Masson SAS. All rights reserved.