Abstract: The systematic and synthetic description and review of lianas,chiefly distributed in tropic,are described and reviewed in this paper,in which some ecological questions of lianas are included as follows:(1) The conception and significances of lianas;(2)Liana flora and its distribution in the world;(3)Its biological characteristics;(4)Its ecological characteristics;(5)Its abundance(density)and species-richness in tropical forest;(6)The ecological significance of lianas-aggregation in gap and the va-fiance of its abundance in the process of forest succession;(7)The relationship between lianas and trees;(8)The positive and the negative contribution of lianas to tropical forest;(9)The types of climbing mechanism of lianas and its competitive predominance;(10)Global climate-variance(CO₂ increase)pro-motes abundance of lianas to increase，and some ecological consequence are resulted from which．