The study investigated the effect of prefermentation of Bifidobacteria longum and Lactobacillus plantarum on baking quality. Firstly, two kinds of prefermentation were cultured using two lactic acid bacteria, Bifidobacteria longum and Lactobacillus plantarum. White pan bread baked with dough that had undergone these two prefermentation methods was compared with that baked with a non-prefermented control. The physicochemical properties of the three breads were analyzed, and then the physicochemical and sensory properties of the dough and baked bread were cross-analyzed. The pH prefermentation of Bifidobacteria longum was lower than that of Lactobacillus plantarum, whereas the titratable acidity was higher. Compared to the results from analyzing the prefermentation of Lactobacillus plantarum, the prefermentation of Bifidobacteria longum was expected to give positive effects on enriching the bread flavor by creating acetic acid at a level three- to eight-fold higher than that of Lactobacillus plantarum. According to the mixogram data, the optimum ending time for both Bifidobacteria longum prefermentation and Lactobacillus plantarum was around 4.5 to 5 minutes. The speed of dough materialization decreased with increasing prefermentation culture time. The baked bread with added Bifidobacteria longum had a higher water content. However, the other contents were not influenced by prefermentation, but were by culture time. The specific loaf volume, oven spring and baking lass rate all peaked at 20 hours after culture for both prefermentation cultures. The sensory test results indicated the highest prefermentation for the bread baked with prefermented Bifidobacteria longum doughwith a culture time ranging from 20 to 26 hours. In addition, the bread baked with prefermented Lactobacillus plantarum dough gave the highest preference when cultured for 20 hours.