This study leverages social media data from X.com and advanced deep learning techniques to analyze public perception of climate and environmental issues in the Mekong Delta. A dataset of 3,009 tweets collected in May 2024 was analyzed using BERTopic to identify key themes, revealing prominent topics related to water governance, climate change resilience, biodiversity, flood management, agriculture, tourism, and hydropower impacts. These topics were grouped into three themes: (1) hydropower impact and regional tensions; (2) water governance and environmental resilience; and (3) climate change and agricultural impacts. Subsequently, BERT was used for sentiment analysis to classify the sentiments within these topics into positive, negative, and neutral categories. The sentiment analysis indicated that negative sentiment is higher compared to positive and neutral sentiments, with an increasing trend over time. The findings contribute to the academic understanding of social media’s role in environmental discourse and offer practical implications for policymakers and stakeholders in the Mekong Delta. This research underscores the potential of leveraging digital platforms and advanced analytical methods to gain valuable insights for effective climate adaptation and environmental management strategies.