For more than seventy years, the Sino-Indo border crisis has become an endless imbroglio with no settlement in sight. Relations between the two Asian giants have soured over the last decade, particularly following a 2020 boundary skirmish between Indian and Chinese soldiers in the Galwan area. The issue of a disputed border emerged in the early 1950s when the People’s Republic of China affected her capture of Tibet. This act created for China and India one of the lengthiest undefined boundaries in the globe. The China-India border stretches for approximately 3,488 kilometers (2,167 miles) across the Himalayan mountain range, separating the two countries. The main areas of contention are the western sector (Aksai Chin region administered by China but claimed by India) and the eastern sector (Arunachal Pradesh region administered by India but claimed by China). This dispute has led to several military standoffs and border skirmishes between the two countries over the years. The intricate and protractedness of this border conflict made this work try to find out the causes and implications of this crisis to the Asian region and the world generally. To do this effectively, we employ secondary sources where data was collected from textbooks, diplomatic records, academic literature, newspapers, journals, magazines, and internet materials. The data collected was analyzed through documentary evidence while the contested border and territorial nationalism theory were used as the analytical tool. The work discovered that factors like unresolved border issues, historical crises, strategic concerns, ideological biases, failed diplomatic negotiations, military considerations, the Tibetan refugees crisis, Cold War dynamics, and limited communications were some of the issues that led to the border crisis between the two Asian giants. Furthermore, the work found out that the implications engendered by the China-India border crisis are severe and expansive like heavy militarization of the China-Indian border, strategic instability in Asia, India’s more assertive foreign policy, China’s global image damage, policy implications, and arms race between the two Asian giants. The work concluded that China and India should strive for a harmonious and sustainable joint boundary commission that will map and mark their boundaries as this option if meticulously and strictly followed will tremendously benefit both and all.