Bengt Jangfeldt has been specializing in Russian literature for 30 years. His doctoral thesis (1976) treated the relationship between the Soviet State and the literary avant-garde during the years of the revolution, 1917-1921. This work was later supplemented by a series of archival editions.

Professor Jangfeldt has collected and published the correspondence between Vladimir Mayakovsky and Lili Brik (in Russian in 1982 and 1991, in English in 1986: "Love is the Heart of Everything") as well as the literary legacy of the great Russian linguist, Roman Jakobson (Russian edition 1992, English edition 1997: "My Futurist Years"). During the last ten years he has been focusing on the historical ties between Sweden and the St. Petersburg region. This work has resulted in several books, including Svenska vägar till S:t Petersburg
which in 1998 was awarded the August Prize (the Swedish equivalent of the Booker Prize). His last books include an authorised biography of the Swedish author and doctor Axel Munthe (En osalig ande, 2003).

Bengt Jangfeldt has translated many of Joseph Brodsky's works into Swedish, the poetry from Russian and the prose from English. In 1988, he was awarded the Letterstedt Prize for Translation by the Royal Swedish Academy of Sciences for rendering into Swedish Brodsky's book of essays, "Less
Than One".