China’s ambitious goal “strive to peak carbon emissions before 2030 and achieve carbon neutrality before 2060” not only shows China’s responsible attitude towards climate change, but also aligns with the upgrade requirement of China’s economy and industries. Since cities occupy a dominant position in China’s population, energy consumption, and carbon emissions, they are the main battlefield for achieving national carbon neutrality. This study first analyzes the challenges and requirements that cities’ energy systems facing in order to realize carbon neutrality. Then, it takes Macao as an example to analyze the characteristics of cities’ energy consumption and carbon emissions. Finally, it proposes a pathway to realize cities’ carbon neutrality that include four major measures: promote demand-side management in cities’ energy systems; encourage distributed clean energy integration; actively purchase clean electricity from outside of cities; and leverage intelligent techniques for urban energy systems operation & optimization. The proposed pathway can provide a reference for promoting the carbon neutrality for China’s cities.