The paper offers an analysis and a classification of lexicographic works on Tibetan medicine compiled by Mongolian and Buryat authors in the 18-20th centuries. The analysis of main topics of these works and of their terminology allow us to distinguish three types of dictionaries: (1) specialized mngon brjod dictionaries of synonyms of Tibetan materia medica compiled for their correct identification; (2) bilingual and monolingual bsdus ming glossaries that contain explanations of words and concepts of the rgyud bzhi and commentaries; and (3) general and terminological brda yig dictionaries with medical lexicons. Particular attention is paid to distinctive features of these dictionaries. The study reveals that words in all thesauruses compiled by Mongolian authors and in the terminological dictionary dag yig mkhas pa’i ‘byung gnas (18th century) are arranged by thematic groups. The words in all bsdus ming glossaries are limited to the lexis used in one particular treatise and arranged in order in which they occur in the text. All lexicographical works compiled by Buryat authors (dictionaries of Tuguldurov, Sumatiratna, and Choidak) were organized according to Tibetan alphabetical order. In the rgyud bzhi bsdus ming and in the dictionary of Ishdorji all Mongolian equivalents are given in Tibetan letters. The study shows that dividing dictionaries of Mongolian authors in three groups (in accordance with their topic, basic terms, basic principles of compiling dictionaries of a certain genre) allows us to trace the continuity of the Indo-Tibetan lexicographic tradition in Mongolia and Buryatia, and also to demonstrate significant contribution of the Buryat scientists to the development of Tibet lexicography (concerning alphabetical principle of dictionaries compilation).