The purpose of this investigation was to study the effects of aluminosilicates (vermiculite and bentonite), added to feed on thallium bioaccumulation in laying hens. The experiment was conducted on 48 layers kept in cages under vivarium conditions. The hens were divided into 4 groups: Group 1- control, Group 2 - thallium-intoxicated, Group 3 - thallium-intoxicated fed on feed containing vermiculite and Group 4 - thallium-intoxicated fed on feed containing bentonite. Thallium was added in the form of sulphate (Tl₂SO₄) at a daily dose of 0.74 mg/kg body weight. Thallium content was determined in blood and eggs on days 1, 14, 28, 42, 56 of the experiment and also in thigh and breast muscles, kidney, liver and thigh bone after the experiment was accomplished. Thallium content of the tissues and organs was determined using plasma spectrometry ICP-MS. The highest thallium concentration was found in bones 8.849 mg/kg, next in kidneys 7.596 mg/kg. Lower thallium content was found in muscles, liver and blood. The addition of bentonite reduce thallium accumulation most effective in muscles by 34.75-36.94% and blood 39.07%. The addition of vermiculite to the feed had reducing impact on thallium accumulation in the all tested tissues and organs of birds chronically intoxicated with this element (by 18.2% in kidneys - 55.71% in breast muscles).