Semi-hard and hard ripening cheeses were examined after being salted in a 20% solution of sodium chloride or sodium chloride and potassium chloride mixture (1:1 w/w) for 25 and 100% standard salting time. Bioavailability of magnesium from the cheese diets, as expressed in the terms of apparent absorption and retention, and liver and blood levels of magnesium, was determined in growing Wistar rats during 6-week experiment. The addition of potassium chloride to brine was found to decrease significantly the intake of magnesium for rats fed diets with examined cheeses. The type of cheese, composition of brine, salting time and interactions of these factors significantly influenced the values of apparent absorption and retention of magnesium. The content of magnesium in the liver of rats was dependent on the type of cheese and that in the blood plasma was dependent on the composition of brine used for cheese salting. Feeding rats diets with the cheeses being salted in the mixture of the chlorides did not cause more serious disturbances in absorption and metabolism of magnesium in rats.