OBJECTIVE： To evaluate the in vitro antibacterial， anti-inflammatory and immunopotentiating activity of An’erning granules. METHODS： Micro-dilution method was used to determine the minimum inhibitory concentration（MIC）of An’erning granules （1.562 5-100 mg/mL） on 10 kinds of common pathogenic bacteria. Using RAW 264.7 cells （mono-nuclear macrophage） as objects， LPS was used to replicate inflammation model. MTT assay was used to investigate the effects of An’erning granules （0.312 5-20 mg/mL） on proliferation and the release of NO of macrophage. Using spleen lymphocyte of BALB/c mice as objects， MTT assay was used to investigate the effects of An’erning granules （0.312 5-20 mg/mL） on lymphocyte proliferation. RESULTS： MIC of An’erning granules to Epidermis staphylococcus and Streptococcus pneumoniae was 6.25 mg/mL； MIC of An’erning granules to Proteus vulgaris， Klebsiella pneumoniae， Bacillus subtilis and Escherichia coli （standard strain） were 12.5 mg/mL； MIC of An’erning granules to Pseudomonas aeruginosa， Enterococcus faecalis and Bacillus cereus were 25 mg/mL； MIC of An’erning granules to E. coli （clinical isolates） and Salmonella typhia were 50 mg/mL. Compared with LPS model group， An’erning granules could significantly reduce the LPS-induced release of NO in RAW 264.7 cells at the dose of 0.312 5-1.25 mg/mL （P＜0.05）. Compared with blank control group， An’erning granule had no interference on the proliferation of RAW 264.7 cells and spleen lymphocytes of mice or had a tendency to promote proliferation. It could significantly promote lymphocyte proliferation at doses of 0.625 and 0.312 5 mg/mL （P＜0.05）. CONCLUSIONS： An’erning granules not only have certain in vitro inhibitory effects on clinical common Gram-positive and Gram-negative pathogenic bacteria， but also have anti-inflammatory and immunization enhancement effects.