Implementation of GST increased the tax revenue and this helps the government to provide better services encouraging production and increasing Economy-GDP. This micro-study seeks to analyze the relationship between Economy-GDP and GST Revenue and the influence of the Cost of GST Collection on such relationship which was unexplored in the previous studies. The study offers insights to the policymakers in ensuring the efficient generation of GST Revenue and making decisions related to Taxation, Spending, and Economic Planning. For the Study, Data were collected from Secondary Sources such as the Union Budget of India and the Press Information Bureau. A Statistical Model was framed using the data collected from the Secondary Sources. The Statistical Model WAS analyzed with the help of Multiple Regression Analysis Via Process macro model number 1 using SPSS Software. The results showed a significant relationship between Economy-GDP and GST Revenue. However, it was found that the relationship between EconomyGDP and GST Revenue remained stable across the levels of the Cost of GST Collection. Considering the sample size taken for the study, further research is essential to get more insights from this study.