Background: Persistent diarrhoea (diarrhoea lasting more than 14 days) accounts for one third of all diarrhoea related deaths in developing countries in some studies. Probiotics may help treatment. Objectives: To evaluate probiotics for treating persistent diarrhoea in children. Search methods: We searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL, MEDLINE, EMBASE, and LILACS. We also contacted authors of included trials and organizations working in the field, and checked reference lists. The date of the most recent search was 13 December 2012 Selection criteria: Randomized controlled trials comparing a specified probiotic agent with placebo or no probiotic in children with persistent diarrhoea. Data collection and analysis: Two review authors assessed the eligibility, risk of bias, extracted and analysed data. Differences were resolved by discussion. Statistical analysis were performed using the fixed-effect model and the results were expressed as mean difference (MD) for continuous outcomes with 95% confidence intervals (CI). Main results: Four trials were included, with a total number of 464 participants; one trial had a low risk of bias. Meta-analysis showed that probiotics reduced the duration of persistent diarrhoea (mean difference 4.02 days, 95% CI 4.61 to 3.43 days, n = 324, two trials). Stool frequency was reduced with probiotics in two trials. One trial reported a shorter hospital stay, which was significant, but numbers were small. No adverse events were reported. Authors' conclusions: There is limited evidence suggesting probiotics may be effective in treating persistent diarrhoea in children.