This article primarily investigates the effectiveness of the Grammar Translation Method (GTM), one of the most traditional methods in the pedagogical application of teaching English as a second language (L2). Despite being traditional, GTM is being widely used in L2 instructional settings, particularly at tertiary level education. Though there is no conclusive evidence to suggest that GTM was initially based on specific theoretical framework, its predominant techniques including translation and memorization still play a crucial role in second language teaching process. The current study, a part of an action research, was conducted at Buddhist and Pali University of Sri Lanka with a sample of sixty students selected purposively, who were exposed to selected techniques of GTM pedagogy. This qualitative study employed a pre-test post-test quasi-experimental research design. A paired-sample t-test was used to compare the mean value difference: significant p-value (p < 0.005) indicates the efficacy of GTM in the pedagogical application. These results suggest that vital techniques of GTM can be effectively incorporated into current pedagogical practices to maximize the learning outcomes.