Abstract The contribution deals with optimisation of cold bonded pellets production from BOF sludges and dusts for reductive melting treatment in pig iron. The experiments were carried out in laboratory scale. The mixture for pellets production consists of BOF sludges and dusts, fine coke, and cement. The pellets were produced in balling disc with diameter 1020mm. The determination of pellets strength was carried out after pellet production and every day in time of 3 weeks. The pellet strength was in range from 9 to 43 N per pellet. The influence of shortened drying way on strength of produced pellets at temperature 95°C was observed, too. The strength of free dried pellets was much higher than pre-dried pellets after 2 days. The results showed that maximal strength of pellets was reached up to 7 days (1st phase). In 2nd phase, which takes 7 days, too, the strength of pellets has constant value. In 3rd phase, which occurs after another 7 days, the decreasing of pellet strength is observed.