The invention provides rhizoma alismatis granules with the efficacies of removing and preventing
urinary calculus used for preventing and treating
urinary calculus. A preparation method of the rhizoma alismatis granules comprises the following steps: taking the five medicinal materials, including rhizoma alismatis, herba plantaginis, herba desmodii styracifolii, poria cocos and
cassia twig as the raw materials, adding with 8-fold amount of water, decocting the medicinal materials for twice, wherein each time is 2h, mixing the decoctions, filtering the obtained mixed decoction, concentrating the filtrate to obtain extract, adding with 1.5-fold amount of
dextrin and 0.004-fold amount of steviosin, carrying out uniform mixing by adopting 80%
alcohol as a
wetting agent (the use amount of
alcohol is 10% of that of the extract), and preparing the granules by adopting a conventional method. A quality detection method is characterized in that a thin-layer
chromatography of herba desmodii styracifolii and
cassia twig in the medicinal materials is adopted as an identification method, specifically, the contents of two active ingredients, namely, plantamajoside and
schaftoside in the medicinal materials are measured by adopting a
high performance liquid chromatography. The product is used for preventing and treating
urinary calculus, and an extraction process is simple, stable and feasible; a
quality standard detection method of the rhizoma alismatis granules with the efficacies of removing and preventing urinary calculus is sensitive and reliable and is strong in specificity.