The present invention relates to a novel bicyclic derivative that has an inhibitory activity against sodium-glucose linked transporters (SGLTs) present in the intestines and kidneys, or a pharmaceutically acceptable salt, isomer, hydrate or solvate thereof, and a pharmaceutical composition including the same as an active ingredient, which effectively inhibit the SGLT activity, and thus can be used as a therapeutic agent to treat diseases caused by hyperglycemia, such as diabetes including insulin-dependent diabetes (type I diabetes mellitus) and non-insulin-dependent diabetes (type II diabetes mellitus), diabetic complications, and obesity.
