Cobalt ferrite, copper and bismuth co-substituted cobalt ferrite nanoparticles are prepared by solution combustion method. The synthesized compounds are authenticated by powder X-ray diffraction, Fourier transform infrared spectroscopy, Scanning electron microscopy-Energy dispersive X-ray analyser and Vibrating sample magnetometer. Particle size, lattice parameter, saturation magnetization and coercivity as a function of bismuth and copper substitution in cobalt ferrite nano particles are studied. Lattice parameter and dielectric constant are increased due to the substitution of bismuth in cobalt ferrite. Catalytic activity of the synthesized compounds are tested for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). The conversion of nitrophenol to amino phenol is achieved in seconds using the substituted cobalt ferrite compounds. © 2016, Springer Science+Business Media New York.