The use of probiotics as food components combats not only cardiovascular diseases but also many gastrointestinal tract disorders. Their health benefits along with their increased global market have interested scientists for better formulation and appropriate administration to the consumers. However, the lack of clear elucidation of their cholesterol-lowering mechanisms has complicated their proper dosage and administration to the beneficiaries. In this review, proposed mechanisms of cholesterol reduction such as deconjugation of bile via bile salt hydrolase activity, binding of cholesterol to probiotic cellular surface and incorporation into their cell membrane, production of SCFAs from oligosaccharides, coprecipitation of cholesterol with deconjugated bile, and cholesterol conversion to coprostanol have been discussed. Also, hypocholesterolemic effects on human- and animal-trial results, commonly used probiotics and synbiotics with effect on serum cholesterol regulation, types of bile salt hydrolase genes, and substrate specificities have been discussed.