A core problem in robotics is the localization of a mobile robot (determination of the location or pose) in its environment, since the robot’s behavior depends on its position. In this work, we propose the use of a stationary fisheye camera for real time robot localization in indoor environments. We employ an image formation model for the fisheye camera, which is used for accelerating the segmentation of the robot’s top surface, as well as for calculating the robot’s true position in the real world frame of reference. The proposed robot localization algorithm does not depend on any information from the robot’s sensors and does not require visual landmarks in the indoor environment. Initial results are presented from video sequences and are compared to the ground truth position, obtained by the robot’s sensors. The dependence of the average positional error with the distance from the camera is also measured.