With the pace of time software cost estimation is one of the most tedious works in project management. The entire process of estimation is uncertain in nature because it relies upon some attributes which cannot be predicted during the early stages of development. After studying various research papers given by different researcher we try to explore soft computing techniques which can be able to overcome the uncertainty and imprecision in estimation. The crucial focus of this article is to investigate the importance of fuzzy logic technique in enhancing the effort estimation accuracy, using COCOMO II by characterizing input parameters using various functions for example Gaussian, trapezoidal and triangular membership functions and comparing their results. In our study NASA (93) dataset will also be used in the evaluation of the proposed Fuzzy Logic COCOMO II. After that deep analysis will be done by various membership functions and then will declare which function gives better results for maximum criteria when compared with the other technique.