The invention discloses preparation and quality detection methods of high-purity honeysuckle flower-baikal skullcap root soluble powder. The preparation method comprises the following steps of: 1, preparing an appropriate amount of baikal skullcap root, adding water for decocting for 2-4 times, combining decoctions, filtering, and concentrating the filtrate till the relative density is 1.10-1.35; 2, regulating the pH value to 1.0-2.0 with hydrochloric acid, preserving heat at the temperature 60-80 DEG C, standing, and filtering; 3, adding water into a precipitate, stirring uniformly, and regulating the pH value to 6.5-7.5 with 30-40 percent sodium hydroxide; 4, adding an equal amount of ethanol, stirring for dissolving, filtering, regulating the pH value of the filtrate to 1.0-2.0 with hydrochloric acid, preserving heat at the temperature 60-80 DEG C, standing, and filtering; 5, washing the precipitate with an appropriate amount of water and ethanol of different concentrations in sequence till the pH value is 6.5-7.5; 6, vaporizing the ethanol and drying under reduced pressure to obtain a baikal skullcap root extract; 7, preparing an appropriate amount of honeysuckle flower, adding water for decocting for 1-3 times, combining decoctions, filtering, and concentrating the filtrate under reduced pressure at the temperature 50-70 DEG C till the relative density is 1.10-1.25 to obtain clear paste; 8, adding ethanol till the ethanol content is 80-90 percent, standing for 24 hours, and filtering; 9, adding ethanol into filter residues till the ethanol content is 75-95 percent, standing for 18-30 hours, and filtering; 10, combining two filtrates, recovering ethanol, and concentrating under reduced pressure till the relative density is 1.15-1.30; 11, performing spray drying to obtain a honeysuckle flower extract; and 12, combining the baikal skullcap root extract with the honeysuckle flower extract, adding sodium bicarbonate to fixed amount, adding glucose to fixed amount, and mixing uniformly to obtain the honeysuckle flower-baikal skullcap root soluble powder.