This paper presents an efficient technique for automatic ear detection from side face images. The proposed technique detects ear by exploiting its inherent structural details and is rotation, scale and shape invariant. It can detect ear without any training or assuming prior knowledge of the input image. The technique is based on connected component analysis of a graph constructed using the edge map of the image and is evaluated on a data set consisting of 2361 side face images collected at IIT Kanpur. Ear detection results are found to be very good and speak for the efficiency and robustness of the technique. To show the accuracy of the detection, detected ears are used for recognition and results are compared with the same obtained when ear cropping in done manually.