Carbon nanotubes have fascinating chemical and physical properties as indicated by graphite and diamond characteristics, and the reason is their individual atomic structure. They have acquired critical achievements in various fields such as materials, electronic devices, energy storage, separation, and sensors. Recently, antireflective coatings with self-cleaning properties attract critical consideration for their theoretical characteristics and their wide-ranging applications. In this chapter, the benefits of using CNTs as an antireflection and self-cleaning thin coating layer have been discussed to improve mechanical and electrical behavior of solar cells. Transfer-matrix method (TMM) and finite-difference time-domain (FDTD) method were studied as most suitable technique for thin films. © 2017, Springer International Publishing Switzerland.