Experimental details procured from the resultant strain and stress of steel and concrete which form the major components of geo-polymer concrete beam. While this method is creates real time behavior, it is enormously time utilizing, and the use of materials can be quite expensive. Computer software simulation would aid in future development of the geo-polymer concrete members. The study is to examine the performance of the geo-polymer concrete (GPC) beam, in the various conditions of crack such as initiation, penetration and pattern, flexural strength, load–deflection and other mode of structure failure which exhibits the realistic behaviour when the actual material is used to create the FE model. This work is express the importance of FE modelling in structural element analysis. It can shows the behaviour of geo-polymer concrete beam until failure. It also gives comprehensive results of the element under critical distribution of stresses and effective strains in member and steel reinforcement in the members. To examine the flexural behaviour of geo-polymer concrete beams using three dimensional FEM analysis. Particularly focused on the failure surfaces of geo-polymer reinforced concrete beam and also the physical properties of flexural cracking behaviour of the beam. Procured results from the analytical calculation using ACI codes are compared with FEM analysis. This investigation is to evaluate the incremental loading conditions with respect to the time until failure. In this paper, we are going to analyze the behaviour under reinforced geo-polymer concrete beam with help of the computer analysis which is fail in flexure. The accessibility of nonlinear models with the help of available computer software. Finite element software simulation for structural members is cost effective.