Sulphidic tailings from Finnish Hitura nickel mine and Pyhäsalmi multi-metal mine were leached using sulphuric acid and bioleached. The aim was to recover minor amounts of valuable Cu, Ni, Zn and Mn. Both tailings consisted mainly of iron and magnesium-containing minerals and acid neutralizing minerals. The solution after chemical leaching tests contained mostly iron and magnesium, in Hitura up to 11 g/dm³ Fe and 38 g/dm³ Mg while in Pyhäsalmi 8–9 g/dm³ Fe and 4 g/dm³ Mg. Amount of these metals was 20–100-fold larger than amount of valuable metals, which were typically 100-300 mg/dm³. Problems in chemical leaching were high consumption of acid and poor selectivity. Bioleaching using iron and sulphur oxidizing bacteria was more selective towards the valuable metals. Both in leaching and bioleaching the high concentration of iron and magnesium in solution will make metals recovery challenging.