Strengthening bilateral energy security cooperation is crucial in the process of fostering the sustainable growth of China and neighboring Asian nations. Using data chosen from China and 25 adjacent nations between 2010 and 2019, this article first assesses the level of energy security using the TOPSIS (Technique of Ranking Preference with Similarity to Ideal Solution) and GRA (Grey Relational Analysis) methodologies. Additionally, based on the level of energy security, this article analyzes the coupling degree of bilateral capacity structure and, in the end, suggests a theoretical model to assess the stability of bilateral energy security cooperation. The findings demonstrate that China and its neighboring countries share the energy trilemma, which is the inability of these nations to simultaneously achieve the needs of energy supply security, energy justice, and environmental sustainability. The report also makes the case that Thailand, Kazakhstan, and the Philippines all have theoretically stronger sustainability of bilateral energy security cooperation with China. This study also offers some recommendations for improving bilateral collaboration between China and its neighbors on energy security.