The Kangchenjunga landscape, a transboundary complex shared by Bhutan, India, and Nepal, is one of the biologically richest regions in the Eastern Himalayas. Owing to the remarkable biodiversity, the three countries came together to enhance regional cooperation in conservation and development in 2012. To start a strategic conservation intervention, the status of our knowledge base on biodiversity of the landscape is the most important stepping stone. In this paper, we traced the history of biodiversity research in the Kangchenjunga landscape, and present the research trends over time and subject interests. Meanwhile, we also identified key research and knowledge gaps and future priorities. For this, we analyzed 500 peer-reviewed journal articles (until 2014) relating to biodiversity, which were retrieved from the web platform 'Google Scholar' and other peer-reviewed journals. The review showed that the landscape received attention from the scientific community as early as the 1840s, and grew progressively after the 1980s. Research on fauna (especially mammals) and flora (especially angiosperms) is most notable, but with major gaps in systematic research of their ecology, whereas invertebrates other than butterflies appear to be neglected. There is a need for systematic research with long-term monitoring that would allow us to understand changes occurring within the landscape.