Abstract The effect of montmorillonite (MMT) on dietary lead (Pb) accumulation in tissues of tilapia ( Oreochromis niloticus ) was investigated. Two hundred forty tilapia were randomly divided into four groups and fed with a basal diet, a basal diet supplemented with 0.5% MMT, Pb-contaminated basal diet (100 mg Pb/kg dry mass) and Pb-contaminated basal diet supplemented with 0.5% MMT, respectively. After 60 days, tilapia were sacrificed and sampled to determine Pb accumulation, zinc and iron concentration in the tissues of tilapia. MMT significantly reduced Pb accumulation in kidney, intestine, bone, stomach, gill, liver, spleen, muscle, spermary and brain of tilapia( P P > 0.05). Addition of MMT in diet could protect tilapia from dietary Pb accumulation in tissues.