One of the most important assets for the organization in the current competitive business environment is customer feedback. In today's digital age, customer opinions are more readily available through digital platforms, online reviews, surveys, and social media, helping companies better understand customer expectations, satisfaction, and buying habits. This study focuses on analyzing customer feedback and its impact on marketing effectiveness, with specific reference to Greenline Eco Product Pvt. Ltd. The study is aimed at finding factors affecting customer satisfaction, finding out how customer feedback affects marketing strategies, finding out customer sentiment, and finding the influence of customer trust on marketing performance. It was a descriptive study, and primary data were obtained using 24 respondents from a convenience sampling, which was collected using a structured questionnaire. SPSS software was used to conduct statistical analysis using Percentage Analysis, One-Sample T-Test, Independent Samples T-Test, Mann-Whitney U Test, Paired Samples T-Test, and Wilcoxon Signed-Rank Test. The results showed that feedback from the customers had a significant impact on the effectiveness of the marketing programs, as it can enhance the satisfaction of customers, trust in the brand, and the quality of service. Positive customer feedback aids in the performance of the marketing department and enhances customer loyalty; constructive feedback helps in making strategic decisions and improving the services offered to customers. The study concludes that good analysis of customer feedback makes it possible for organizations to create marketing strategies focused on the customer and help them support their competitive advantage overall.