The present invention relates to iron oxide nanocomposite, magnetic resonance imaging T2 contrast medium compring same, and method for manufacturing same. More particularly, the present invention is directed to An MRI (magnetic resonance imaging) T2 contrast agent, comprising an iron oxide nanocomposite which includes an iron oxide nanoparticle, wherein said iron oxide nanoparticle is encapsulated with a surfactant and said surfactant is encapsulated with polyethylene glycol-phospholipid and method for preparing the same.
