Information of cellular organelle location and morphology is essential for cancer simulation. In order to obtain such information, the segmentation of the organelles from electronic microscopy intracellular image is crucial. In this paper, we focus on the segmentation of mitochondria organelle which is one of the most important organelles tightly related to the form of cancer. A simple three-stage strategy for mitochondrial segmentation based on exclusive and morphology properties and Gabor filter is proposed. Experimental results on focused ion beam (FIB) and scanning electron microscope (SEM) images have shown the effectiveness of proposed method.