Dissotis thollonii (D. thollonii) is traditionally used for the treatment of diarrhoea in Africa. The study aim to evaluate aqueous and methanol extracts of leaves of D. thollonii (Melastomataceae) for their antidiarrhoeal, antibacterial activities as well as probiotics growth stimulation effect. Both extracts effects were evaluated using rat animal models for in vivo assay. Antimicrobial activities were also been evaluated. D. thollonii extracts at all doses (125, 250 and 500 mg/kg) significantly inhibited the mean volume of intestinal fluid in prostaglandin E2 induced enteropooling assay, with the treatment of both extracts similarly to that of the standard antidiarrhoeal drug (loperamide), as well as the significant reduction of electrolytes concentration in the intestinal fluid. There was no inhibition, but rather growth of all probiotics tested. Extracts inhibited growth of 3 reference bacterial strains (Staphylococus aureus NCTC 6571, Bacillus subtili ATCC 23857 and Enterococus feacalis ATCC 39532) with minimum inhibitory concentrations (MIC) of 1000, 500 and 250 μg/ml, corresponding to percentage inhibition of 54.75 ± 0.47, 52.74 ± 4.40, and 50.15 ± 4.72 with methanol extract respectively. We also observed inhibition of one clinical isolate (Helicobacter pylori) with both extract at minimum inhibitory concentrations (MIC) of 2000 μg/ml, corresponding to the inhibition percentage of 54.37 ± 0.60 and 50.33 ± 0.66 respectively to the aqueous and methanolic extract. In vivo, extracts provoqued at all doses, a significant decrease (P<0.001) of the bacterial load in the faeces of rats, during all days of treatment compare to those which was treated with distilled water. Histological examination of the caecum showed at the dose of 250 and 500 mg/kg of aqueous and methanol extract respectively, no degradation of different layers compare to neutral and positive control (ciprofloxacin). These results attested the ethnopharmacological used of D. thollonii leaves in the treatment of diarrhoea and gastro-intestinal infections.