The invention provides a process for preparing lotus leaf extract through macroscopic adsorption resin separation and purification, as well as the use of the extract, the process consists of obtaininglotus leaf extract through film separation and purification, charging water to form suspending liquid, macropore resin adsorbing till saturation, water scrubbing the polarity impurity, eluting and concentrating in vacuum. The obtained lotus leaf extract can be used for preparing medicament having functions of fat-reducing, blood fat lowering, bacterium resisting, detoxicating, drug rehabilitatingand oxidizing. The extract can be prepared into dose forms of capsules, granules, tablets, oral liquids, syrups, tiny capsules, powders or dripping pills.