Rapid urbanization in emerging economies has intensified environmental pressures, including rising energy demand, air pollution, land-use change,climate vulnerability, and infrastructure stress.At the same time, smart urban develop- -ment and climate resilience offer important pathways for improving environmental sustai- -nability. This study examines the influence of smart urban development and climate reilience on environmental sustainability in emerging economies using secondary panel data. The study adopts a quantitative research design and applies panel regression techniques to assess the relationship among smart urban develop- -ment,climate resilience, urbanization, renew- -able energy use, energy intensity, GDP per capita, governance quality, and environmental sustainability. The findings indicate that smart urban development has a positive effect on environmental sustainability, suggesting that digital infrastructure, ICT access, smart monitoring systems, and data-driven urban services can improve environmental performa- -nce. Climate resilience also contributes positively to environmental sustainability by strengthening adaptive capacity, reducing vulnerability, and supporting risk-informed urban planning. Renewable energy use impro- -ves sustainability outcomes, while energy intensity negatively affects environmental performance. The study concludes that emerg- -ing economies can advance environmental sustainability by integrating smart urban technologies with climate-resilient infrastructure, renewable energy systems, inclusive governance, and sustainable urban planning. The findings provide useful policy insights for governments, urban planners, environmental agencies, and development institutions seeking to build greener, smarter, and more resilient cities