Probiotics, live microorganisms that produce a beneficial effect on health, are a possible supplement to a gluten-free diet in the treatment of celiac disease. Several clinical studies have shown that celiac patients treated with probiotics improved their gastrointestinal symptoms. Although the mechanisms of probiotics in celiac disease are unclear, preclinical studies in mice suggest different mechanisms, such as the modulation of the intestinal microbiota and the immune system, or through the production of proteases. We conducted a review of the literature to address the current evidence on the efficacy of probiotics in the treatment of celiac disease, possible mechanisms of action, and areas of interest for future research studies.