OBJECTIVE：To study the effect s of Bifidobacterium combined with L-carnitine on intestinal flora of dysbacteriosis diarrhea model rats. METHODS ：Totally 30 SD rats were randomly divided into blank control group ，model group ，probiotics group（Bifidobacterium triple viable enteric coated capsules 70 mg/mL），L-carnitine group （L-carnitine injection 50 mg/mL）and L-carnitine+probiotics group （L-carnitine injection 50 mg/mL+Bifidobacterium triple viable enteric coated capsules 70 mg/mL）. Except for blank control group ，the rats in other groups were given 50 mg/mL clindamycin phosphate intragastrically （2 mL/rat， once a day ，for 4 consecutive days ）to establish the model of dysbacteriosis diarrhea. On the 5th day of the experiment ，the rats in administration groups were given corresponding drugs intragastrically ，blank control group and model group were given equal volume of normal saline intragastrically ；with the dosage volume of 1 mL/rat，once a day ，for consecutive 7 days. The general situation of rats in each group was observed during the experiment. The feces of normal control group and model group at the end of the modeling and the feces of the rats in administration group after the last administration were collected for genomic DNA extraction，polymerase chain reaction amplification ，library construction and high-throughput sequencing. After processing ，the effective data were analyzed by operational taxonomic unitsclustering and species annotation ，as well as Alpha and Beta diversity of compared with blank control group ，grade 1 feces and grade 2feces were found in model group. The diversity and richness of intestinal flora ，the ratio of Firmicutes/Bacteroidetes and zhongjuanwang7@163.com the abundance of probiotics such as Lactobacillus， Bifidobacterium and Ackermann were significantly decreased （P＜0.05），while the abundance of pathogenic bacteria such as Enterococcus was significantly increased （P＜0.05）. At the end of the recovery period ，compared with model group ，the activity，fecal morphology and color of rats in probiotics group ，L-carnitine group and L-carnitine+probiotics group returned to normal，and the diversity and richness of intestinal flora had no significant difference （P＞0.05）. However ，the abundance of Lactobacillus in intestinal tract was increased to a certain extent ，and the abundance of Ackermann in intestinal tract of rats in L-carnitine+probiotics group was significantly increased （P＜0.05）. CONCLUSIONS ：Although Bifidobacterium combined with L-carnitine have no significant effect on improving the diversity and richness of intestinal flora in dysbacteriosis diarrhea model rats，it could increase the abundance of probiotics to a certain extent.