A series of CaTa x Zr (1−x) O (3−x) N x solid solutions were successfully synthesized through nitriding precursors prepared by the polymerized complex method. The physicochemical properties of these multicomponent semiconductors were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), N 2 adsorption–desorption isotherms, UV–visible optical absorption spectra (UV–Vis) and density functional theory (DFT) calculations. The diffraction peaks in XRD patterns gradually shifted to higher angles as x increased, indicating that CaTa x Zr (1−x) O (3−x) N x solid solutions had been formed. The absorption edges in UV–Vis spectra red-shifted monotonically as x increased, demonstrating that the band gap of the prepared photocatalysts could be precisely controlled with the adjustment of compositions. The solid solutions rendered photocatalytic H 2 evolution from a formic acid aqueous solution under visible-light irradiation. The narrow band gap, sufficient crystallization, enough pore volume and large specific surface area resulted in the best photocatalytic activity of CaTa 0.8 Zr 0.2 O 2.2 N 0.8 .