This study was investigated the effects of feeding the combination with Lactobacillus plantarum and Bacillus subtilis on the diarrhea incidence and fecal microflora of weaned calves. A total of 12 newly weaned calves were allocated to two dietary treatments in a randomized design based on body weight. The dietary treatments included a commercial basal diet supplemented with: 1) no microbial inoculants (Control); 2) a mixture of Lactobacillus plantarum and Bacillus subtilis (LB). Calves were fed diets for a 4-week period. At the end of the experiment, the counts of fecal lactic acid bacteria and Enterobacteriaceae in LB were significantly improved compared to control (P<0.05). Over the 4-week period, fecal scores and duration of diarrhea in LB were significantly decreased compared with those in control (P<0.05). The present results suggest that LB is a potential feed additive which could be used for the balance of intestinal microflora and the prevention of diarrhea in Korean native calves.