Despite growing concern about the potential adverse effects of elevated nickel concentrations in the environment, only a few toxicity data are available for terrestrial invertebrates. Therefore, chronic toxicity of nickel was assessed for Eisenia fetida, Enchytraeus albidus and Folsomia candida, the three invertebrates for which standard test protocols are available. The 21 d EC50 for the cocoon production of E. fetida was 362 (241-508) mg Ni/kg dry wt. For the reproduction of E. albidus, a 42 d EC50 of 275 (217-346) mg Ni/kg dry wt was observed. The 28 d EC50 for the reproduction of F. candida was 476 (347-671) mg Ni/kg dry wt. The obtained toxicity data were very similar to those of related species reported in literature. Although the presented data can be considered as a step forward in the assessment of the potential risks of nickel in terrestrial environments, further research is needed to evaluate the influence of soil parameters on the toxicity of nickel and to quantify the effect of ageing on bioavailability.