Magnetic nano-composites are multi-component materials, typically containing nano-metric magnetic materials to trigger the response to an external stimulus (ie, an external static or external magnetic field). So far, the search for novel nano-composites has led to the combination of a plethora of different materials (eg, gels, liquid crystals, renewable polymers, silica, carbon or organic metal structures) with various types of magnetic particles, only for fundamental research, but also for application in various fields, including medical therapy and diagnosis, separations, performance or catalysis. In this review, we have selected some of the most recent examples to highlight the general concepts and advances in the preparation of magnetic nano-composites and the recent advances in the synthesis of magnetic nanoparticles.