The present invention relates to an apparatus and a method for tracking an object and more specifically, to an apparatus and a method for tracking an object which is able to quickly and precisely extract and track the object within an image. The method for tracking the object comprises the steps of: acquiring an image frame captured by a camera; setting different pattern sizes depending on the distance from the horizon relative to the horizon in the image frame; extracting an object that matches to the pattern while scanning the image frame with the different pattern sizes; and displaying location information of the extracted object in the image frame. [Reference numerals] (AA) Start; (BB) End; (S110) Set an object to be tracked among objects stored in a database; (S120) Obtain an image frame filmed by a camera; (S130) Set the size of the other patterns according to a distance from the horizon to any pixel based on the horizon inside the image frame; (S140) Extract the object matched with the pattern while scanning the image frame with the other pattern size; (S150) Display the position information of the object extracted on the image frame; (S160) Delivery the pattern size information to a next image frame according to the object position information and the position
