Intelligent Reflecting Surface (IRS) has gained a lot of attention for 6G communication systems due to low-cost reconfigurable meta-materials which can smartly control the wireless propagation channel like never before. In this work, we considered a non-line of sight (NLOS) between the base station and the user. We used the moment generating function (MGF) approach to derive the precise closed-form expression of the probability of bit error rate (BER), and an IRS is used to help create a virtual line of sight (LOS). The wireless channel between the base station-IRS and IRS user is considered to be the log-normal fading channel. The Monte-Carlo (MC) simulated results match the derived theoretical expression. We have investigated the system model under various parameters, namely, the number of reflecting elements, and the log-normal fading parameter. Our analysis suggests that the impact of log-normal fading can be minimized by increasing the number of reflecting elements. In addition, BER is also sensitive to the fading parameter.