The human knee joint is very critical and complex joint of human body which is responsible for our optimal daily functions. It consists of various bones – femur, tibia, patella, fibula, different ligaments, cartilages, menisci and muscles. FEM is a very useful tool for the analysis of knee joint and various knee replacement products. In the knee replacement surgery a proper understanding of knee joint biomechanics is essential. Because of certain limitations of experimental studies, FEM analysis process is playing a significance role for prominent understanding of knee biomechanics and produced an effective and impressive tool for total knee replacement (TKR/TKA) or partial knee replacement (PKR/PKA). The aim of this paper is to give a review on FEM analysis of human knee joint and knee prosthesis devices and how much adequate this method for these type of analysis.