The nuclear and infranuclear pathway of eye movement begins from the ocular mo-tor nuclei situated in thebrain stem, where the axons originate and form three ocular motor nerve s. Although each of the ocular motornerves follows a distinct route to reach the end organ, the extraocular muscles, they also have common housings inthe cavernous sinus and at the orbital apex, where part or all of them are frequently and simultaneously affectedby a common disease process. Since the fine details of normal and diseased structures can frequently be seen onradiologic imaging, especially mag-netic resonance (MR) imaging, a knowledge of the basic anatomy invo l ved innuclear and infranuclear eye movement is important. In this description, in addition to the normal nuclear andinfranuclear pathway of eye movement, we have noted the radio-logic findings of typical diseases involving eachsegment of the nuclear and infranu-clear pathway, particularly as seen on magnetic resonance images. Briefcomments on ocular motor pseudopalsy, which mimics ocular motor palsy, are also included.