In vivo and in vitro trials were conducted to test the efficacy of four aluminosilicates (AS) (Ethacal(R) feed component, Novasil, Perlite, and Zeobrite) to sorb aflatoxin B1 (AFB1) and alleviate aflatoxicosis in broiler chicks. Percentage sorption capacity of AS to radiolabeled AFB1 dissolved in methanol varied from 2 to 60%, whereas percentage sorption in intestinal contents varied from 0 to 40.0% according to type of AS tested. Intestinal contents alone sorbed 42% radiolabeled AFB1. Novasil and Zeobrite exhibited the highest rates of sorption (55 and 60%, respectively) in methanol. An in vivo study compared the four types of AS in combination with 0 or 2.5 ppm AFB1 fed to day-old chicks (two pens of six chicks per treatment) to 3 wk of age. Diet effects on body weight, liver lipid, bone ash, and serum Ca, P, Na, K, and Cl were measured. The AFB1 significantly decreased 2- and 3-wk body weight, and a significant interaction effect of AS and AFB1 on bird weight occurred at 2 and 3 wk of age. Three of the four AS tested alleviated the growth depression caused by AFB1. Liver lipids percentage was increased in the AFB1-treated chicks, but this effect was suppressed by three of the AS. Bone ash was not affected by AFB1 and was increased by Novasil and decreased by Ethacal(R). Ethacal(R), Novasil, Perlite, and Zeobrite all tended to decrease serum Cl, regardless of AFB treatment.