Editorial on the Research TopicProbiotics and constipation This Research Topic mainly focuses on the attenuation effect and potential mechanism of new probiotics on constipation. To date, five papers, including four research articles and one review article have been collected in this Research Topic. Bacillus coagulans BC01, Bifidobacterium lactis TY-S01, and Lactobacillus plantarum KFY02 increased the fecal moisture and gastrointestinal transit rate in mice (Zhou et al., Tang et al. and Yi et al.). Furthermore, the authors found that these strains can promote the homeostasis of gut microbiota in the constipated mice (Zhou et al., Tang et al., and Yi et al.). Bifidobacterium lactis TY-S01 and Lactobacillus plantarum KFY02 increase the community richness and bacterial diversity. More importantly, the structure and composition of intestinal flora in the constipated mice are markedly changed by these three strains, and the change in the abundance of special species depends on the strain specificity of probiotics. The mechanisms underlying these effects on constipation are summarized as follows.