Lopen Dorji Gyeltshen began his professional career with the Loden Foundation, where, in collaboration with the National Library & Archives of Bhutan, he led a digitization team responsible for preserving Buddhist scriptures and archival materials. The team digitized invaluable collections housed in dzongs (fortresses), monasteries, temples, and private collections belonging to aristocratic families as well as individual custodians across Bhutan's remote and rugged regions. He also played a key role in developing Bhutan's Cultural Typology and participated in the nationwide documentation of the country's Intangible Cultural Heritage (ICH) across all 20 dzongkhags. The documentation, carried out in audio, visual, and written formats, has made a significant contribution to the preservation, management, dissemination, and safeguarding of Bhutan's living cultural heritage, benefiting both local communities and the Department of Culture and Dzongkha Development.
Lopen Dorji Gyeltshen later joined the College of Language and Culture Studies in Taktse, Trongsa, where he taught Buddhist philosophy and literature. During his tenure, he also served as the Head of the Rigzhung Department and Coordinator of the Research Centre for Buddhist Studies, contributing to academic research and institutional development. He has authored and co-authored several scholarly publications, translated and edited numerous Buddhist treatises and books, and most recently published the Teacher and Student Manual for Dzongkha Academic Skills. He has since returned to the Loden Foundation, where he currently leads the organization's cultural programmes, focusing on the preservation, promotion, and documentation of Bhutan's cultural and religious heritage.