Background/aim: The effects of aluminium exposure on reproductive biomarkers in male rats were followed in a three-generation study. Materials and methods: Forty Wistar male rats (F0) were divided into the following groups: control (C), receiving only tap water, and three experimental (E) groups, receiving aluminium sulphate (AS) (E1: 200 ppb, E2: 400 ppb, and E3: 1000 ppb) in drinking water for a 6-month exposure period. To obtain F1, three males from each group were mated with previously unexposed females (1:2 sex ratios) that during gestation and lactation were exposed to the same AS levels as males. The F1 generation male offspring were divided as described and exposed to the same AS levels. The protocol to obtain F2 was similar to that described for F1. Results: Significantly lower testosterone levels in rats exposed to AS and in generations F1 and F2 compared to the parental one, luteinising hormone (LH) fluctuations in F0 and a significant LH decrease in F2 and F3 generations, testis weight decrease, increased immobile and abnormal sperm, and histoarchitecture alterations in the testes were observed. Moreover, interval between deliveries increased. Conclusion: Chronic exposure to AS was significantly deleterious, producing a pronounced decrease in the sperm count and testosterone levels in all experimental groups.