1. A subject tracking apparatus comprising: a light detector configured to detect light information based on light from a subject to be tracked at a plurality of light measurement regions in a view of an image, the light information including at least light information detected at a subject region of the subject in the view; a focus detector configured to detect focus information at a plurality of focus detection regions in the view, the focus information including at least focus information detected at the subject region of the subject in the view; and a tracking controller configured to: determine at least one first region having same light information as the light information detected at the subject region from among the plurality of light measurement regions, determine at least one second region having same focus information as the focus information detected at the subject region from among the plurality of focus detection regions, and determine reference information for tracking the subject in the view based on the at least one first region and the at least one second region.