The invention provides a method for extracting and purifying alkaloid in flowers and stems of litsea cubeba. The method comprises the following steps: grinding dried flowers or stems of litsea cubeba, carrying out reflux extraction of total alkaloids by adopting alcohol for 2-4 times, wherein during each time of reflux extraction, alcohol is added according to the feed liquid ratio being 1 to (4-6) g/ml, the extraction time is 1-3 h, mixing the filtrates, concentrating the mixed filtrate and evaporating the solvent, thus obtaining an extract; regulating the extract to be acid and neutral by adopting HCl and stronger ammonia water, carrying out standing for filtration, and finally, regulating the solution to be alkaline by adopting stronger ammonia water, thus obtaining a loading solution; preprocessing a macroporous adsorption resin with the specification of AB-8 or ADS-17, purifying the loading solution, and carrying out elution by adopting alcohol as an eluent, thus obtaining extract of alkaloid in the flowers and stems of litsea cubeba. According to the method for extracting and purifying alkaloid in flowers and stems of litsea cubeba, the extracting method is easy to operate, the alkaloid extracting amount from the flowers and the stems of litsea cubeba is high, the purity is high, the extracting period is short, and complicated experimental apparatuses are not needed, therefore, the cost is low, in addition, the economic value of the flowers of litsea cubeba is improved, and the application field of the flowers of litsea cubeba is expanded.