A comparative study of green construction methodologies between Tamil Nadu palaces and modern practices involves examining the sustainable building techniques employed in traditional palaces in Tamil Nadu, India, and contrasting them with contemporary green construction methods. Traditional palaces often use locally sourced and sustainable materials like wood, stone, lime, and clay. These materials were readily available, reducing transportation-related environmental impacts. Design features such as thick walls, courtyards, and natural ventilation helped regulate indoor temperatures without excessive reliance on external energy sources. Traditional water harvesting systems like step wells and tanks were common in palaces to collect and store rainwater. Modern green building construction materials include recycled steel, bamboo, engineered wood, and sustainable concrete alternatives. Green constructions integrate energy-saving technologies such as solar panels, HVAC systems optimized for efficiency, and intelligent building designs to reduce energy usage. Sustainable water management involves rainwater harvesting, greywater recycling, and efficient plumbing systems to minimize water wastage. Green building design considers the site's natural features, maximizing natural light, and incorporating landscaping for energy efficiency and aesthetic appeal. Green construction focuses on reducing, reusing, and recycling materials. Comparing green construction methodologies between Tamil Nadu palaces and modern practices involves assessing material choices, energy efficiency, water management, design principles and cost implications. Based on the above-mentioned factors this study provides valuable insights into adapting traditional sustainable practices to contemporary construction. I have incorporated the recently renovated Chepauk Palace in Chennai as the case study for the comparison of traditional and modern green construction practices.