Abstarct: Carbon Nanotube (CNT) is an allotrope of carbon. It is a one dimensional nano structure which has various applications in nanotechnology due to its unique electrical, mechanical and thermal features. We don’t exaggerate if name the CNT as the strategic substance of nanotechnology, because sometimes, nanotechnology got known by this significant structure. CNT is formed as a rolled graphite sheet when its diameter is less than ten nanometers and its length is in the order of micrometer. There are two types of CNT: Single-Walled CNT (SWCNT) and Multi-Walled CNT (MWCNT). Single sheet of graphite forms SWCNT and multi sheet graphite forms MWCNT. There are several methods in order to synthesize CNT that each of them has advantages and disadvantages. Depending on the chiral angle (rolling angle) of graphite sheets, CNTs are classified into three types: Zigzag, Armchair and Chiral. Electric conduction is an important feature of CNTs which is also studied in this thesis. CNTs are electrically categorized into two types of mextallic and Semiconducting. This quality is due to their diameter and how they twist, which lead to different band gaps. Although mextallic and semiconducting CNTs are mixed during synthesizing, there are some purification methods to separate them. Necessity of separation of these two types appears due to applications of each type in technologies seems not to be the same. In result, the more purification of mextallic or semiconducting CNTs, the more efficiency in CNT baxsed technologies. Accordingly, several separation methods were proposed. In this thesis Dielectrophoresis method was developed which employ the electrical properties of CNTs under the non-uniform electric field in order to separate mextallic and semiconducting CNTs. Raman spectroscopy, absorbance spectroscopy (UV-vis-NIR) and scanning electron microscopy were applied to characterize the separated CNTs.