Development of theoretical and experimental researches on water vapor absorption into falling film of lithium-bromide/water solution are surveyed, on the basis of analyzing documents home and aboard. Effect of several key factors, such as properties of lithium-bromide/water solution, non-absorbable gases etc. on heat and mass transfer in the falling film absorption are analyzed. Some efficient means, such as surfactant, enhancement equipment, used to enhance heat mass transfer in falling film absorption are respectively analyzed. Some unsolved problems in this area are pointed out and further researches to be performed are consequently suggested in the article.