Nanoparticles of CoxZn1-xFeCrO4 (x = 0.0-1.0) ferrites have been synthesized by the nitrate citrate microwave assisted route. The structural and magnetic properties were investigated by means of X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, vibrating sample magnetometer. X-ray powder diffraction patterns confirm that the samples possess single phase cubic spinel structure. It was found that by increasing the amount of cobalt loading, the crystallite size increases [20-55 nm with increasing the Co content (x)]. The introduction of Cr3+ ions at octahedral B sites results in the dilution of the magnetization at the B site, which will reduce the saturation magnetization. In the opposite way, replacement of non-magnetic Zn2+ ions with ferromagnetic Co2+ ones increases the saturation magnetization of the samples further.