Boris Grigorevich Kolker (Russian: Борис Григорьевич Колкер; born July 15, 1939, in Tiraspol, Moldavian ASSR, Soviet Union) is a language teacher, translator and advocate of the international language Esperanto.

Due to the great popularity of his book eo:Vojaĝo en Esperanto-lando (Travels in Esperanto-Land), which is both a proficiency course in Esperanto and a guidebook to Esperanto culture, he is known to many as a guide to Esperanto-Land.

For two decades he headed a large-scale Esperanto correspondence course in Russia that graduated around 900 students.

He also taught Esperanto at American universities in San Francisco and Hartford.

He has lectured and spoken publicly at several World Congresses of Esperanto and in 2000 he directed the theme of the 85th World Congress of Esperanto in Tel-Aviv.