BACKGROUND: The aim of this review is to provide an insight to the underlying biomedical applications of magnetic nanoparticles (MNPs). METHODS: The most specific characteristic of MNPs is their response to an applied magnetic force, and this property of MNPs has been utilized in applications such as diagnosis of diseases, drug delivery and drug targeting. Currently, MNPs have attracted great attention because of their potential as contrast agents for magnetic resonance imaging (MRI) and heat mediators for cancer therapy (hyperthermia). RESULTS: Furthermore, the MNPs are also being used to achieve targeted delivery of biological molecules. Nowadays cancer is one of the biggest challenges and our goal is not only to improve the therapeutic outcome, but also to improve the methods of treatment along with the minimum adverse effect. Some suitable conclusions have been quoted on the precise synthesis approaches by focusing the mechanism of MNPs and new modification made on the production of these nanoparticles. CONCLUSION: In this review diverse biomedical application of MNPs were also addressed and patents related remarks also made from the literature.