To analyze the target population of Yinhua Miyanling tablet in the treatment of patients with urinary system obstruction and the characteristics of prescription.Methods:Based on HIS large-scale integrated data warehouse,information of 823 patients with UTO treated with Yinhua Miyanling tablets from February,2006 to December,2015 was extracted from 16 large grade-A comprehensive hospitals in China.Association rule analysis based on Apriori algorithm was used to analyze clinical prescription information.Results:After analyzing HIS database,the proportion of female patients with urinary system obstruction was higher than that of male patients(61.10% vs 38.90%),especially in the age group of 45～65.All patients were often complicated with urinary calculi and other diseases.The single dose of Yinhua Miyanling tablets was mainly 2 g(4 tablets),and the daily dose of 2.5～4 g (5～8 tablets) took up 87.99%; 74.50% of the patients were treated for less than 7 days; 97% were cured and improved after discharge.Conclusion:Urinary system obstruction caused by inflammatory reaction is the target treatment group of Yinhua Miyanling tablets.The treatment of 91.7% patients with urinary system obstruction with Yinhua Miyanling tablet needs to be combined with antibiotics.The combination regimen with antibiotics can be further chosen with Yinhua Miyanling combined with penicillin and amtraunan,Yinhua Miyanling tablets combined with penicillin and cefdinir,or Yinhua Miyanling tablets combined with piperacillin sodium and sulbactam sodium,according to drug sensitivity test results.Nearly half of the patients with urinary system obstruction needed to be treated with Chinese medicine clearing the heat; 20.90% needed to be treated with combined tonifying Chinese medicine,and 11.06% with combined freeing strangury and removing stone drugs.