MRI plays a unique role in cancer treatment from three perspectives: Firstly, MRI has superior soft tissue resolution, which makes it indispensible in delineating, staging and monitoring treatment efficacy for certain tumors; Secondly, several techniques which use real-time MRI to map such physiological parameters as temperature, water content or pH have been developed to guide course of anticancer therapies; Thirdly, different targeted probes or hybrid nanoparticles are being developed to facilitate the diagnosis and treatment of tumor under guidance of MRI. In this review article, we will briefly review the first two aspects of MRI guided cancer therapy, followed by a more comprehensive review on the third part focusing on targeted MR imaging probes for personalized medicine.