A method for extracting geniposide from Gardenia jasminoides Ellis by aqueous solution of choline- based ionic liquid was studied. The conditions of extracting geniposide were optimized by single factor and orthogonal experiments. The optimal conditions were as follows : 1.5% cholinium histidinate ( ChOH- His) aqueous solution, solid-liquid ratio of 1:20, oil-bath temperature of 120 %, extraction time of 1.5 h. Under the conditions, the extracting yield of geniposide reached 19.53%, which was 34.3% ...