Magnetic nanoparticles (MNPs) are very attractive especially for biomedical applications, among which, iron oxide nanoparticles have received substantial attention in the past decade due to the elemental composition that makes them biocompatible and degradable. However recently, other magnetic nanomaterials such as spinel ferrites that can provide improved magnetic properties such as coercivity and anisotropy without compromising on inherent advantages of iron oxide nanoparticles are being researched for better applicability of MNPs. Among various spinel ferrites, cobalt ferrite (CoFeO) nanoparticles (NPs) are one of the most explored MNPs. Therefore, the intention of this article is to provide a comprehensive review of CoFeO NPs and their inherent properties that make them exceptional candidates, different synthesis methods that influence their properties, and applications of CoFeO NPs and their relevant applications that have been considered in biotechnology and bioengineering.