Recovery of manganese from spent batteries was investigated using activated carbon powder as a reducing agent in sulfuric acid solution. The effects of four different leaching parameters (sulfuric acid concentration, amount of activated carbon powder, temperature and time) on the leaching of manganese from spent batteries were investigated using central composite design technique. The maximum manganese recovery conditions were determined as 1 M of sulfuric acid concentration, 3 g of activated carbon powder, 80 degrees C of temperature and 3 h of leaching time. Under these conditions, the recovery of manganese was 86.39 % and pH value of the solution was 0.77. According to the reductive acid leaching results, an empirical second order equation for manganese recovery based on four investigated parameters was calculated. The observed values of manganese recoveries using model equation were found to be in a good agreement with the predicted values (R-2 = 0.92).