Objective: To explore the clinical application of appropriate examination technology in precision laboratory diagnosis by testing whether there were intestinal fluid and intestinal contents in abdominal drainage fluid. Methods: Integrated common, simple, rapid and effective testing items to carry out precision laboratory diagnosis. First, the abdominal drainage liquid was mixed well and observed its appearance, then the specimen was centrifuged and separated the supernatant to detect the concentration of amylase and bile acid. The sediment was either taken for direct microscopic examination or prepared as dry slices for Gram dyeing. Finally, we draw a conclusion about whether there were intestinal contents based on the following results and other laboratory results.Results: Routine examination and morphology of the abdominal drainage fluid: the appearance was brown and turbid,Protein qualitative examination: positive (+++), cell lysis fragments was observed and thus the number of cells could not be counted. Microscopic results: Cells were lysed, a large number of bacteria and a small number of cocci were observed. Besides, there were also bilirubin crystals and lipid droplets. Biochemistry results: Amylase 1120U/L, bile acid 25μmol/L. Both the content of amylase and bile acid were 5 times to the patient’s own serum level respectively. Sediment results：The plant cells and plant fibers were found. Conclusion: The detection of plant cells, plant fibers in the wet sediment of drainage fluid is the basis for morphological diagnosis of intestinal contents in the drainage fluid.The results of amylase and bile acid in the drainage fluid were five times higher than those in the patient's own serum control, which was the basis for biochemical diagnosis of intestinal fluid. Therefore, the abdominal drainage fluid could be distinguished from intestinal fluid and intestinal contents by the above multi-parameter appropriate examination technology and results analysis.