A belt conveyor’s drainage system for a concave conveyor belt used for raw material transportation such as coal and grains is installed in the open so that it completely and quickly drains any pool of water due to rainwater.   1. Enables smooth and rapid emission of a water pool from the conveyor belt 2. Reduces idle belt operation time 3. Reduces any damage to the product due to water absorption while repressing blockage and fall-off of cargoes 4. Improves the life span of the facility 5. Saves the necessary motor drive by eliminating tensile power of the belt supported in the operating carrier roller section. 6. Keeps a certain section for reverse V shape section that is attached to pressure roller to prevent remaining water from occurring.   <Cola bottle shape rainwater elimination device>