The flammability of lignocellulose poses a great challenge to its application in textile, architecture and decoration. In this paper, two kinds of deep eutectic solvents were used to modify lignocellulose, and then loaded with ammonium polyphosphate- alumina hydroxide (APP-ATH) double effect flame retardant to prepare flame retardant composites. The results show that the modified lignocellulosic surface groups change through FTIR spectra, and the surface of modified lignocellulosic is rough, and the amount of flame retardant loaded lignocellulose increases with the increase of flame retardant content in SEM images. Through cone calorimeter experiment, compared with pure lignocellulose, the flame retardancy of the lignocellulose based ammonium polyphosphate/aluminum hydroxide (LPA) composites prepared with the modified loaded flame retardants is obvious. The bending strength of choline chloride/cardano system is higher than that of choline chloride/ethylene glycol/oxalic acid system, and the bending strength of choline chloride/cardano system is higher than that of pure lignocellulose. This work make the application of lignocellulosic flame retardancy more extensive and in-depth.