The mechanism of behaviour of parameters involved in protection of the cell from oxidative damage in burn disease remains unclear. Therefore, selenium and lipid peroxide (MDA) levels, and glutathione peroxidase (GSH-Px) activities have been measured for one month in plasma of thermally injured young pigs. Immediately post-burn mean MDA level and GSH-Px activity decreased, while Se concentration increased. After 3 week lipid peroxide levels reached top concentration. Only the enzyme activity returned to initial value at the end of the study, whereas the other two parameters were below the content noted at the beginning. The Se concentration was significantly and positively correlated with GSH-Px activity, and negatively with MDA levels. The similar relationship was also showed for the enzyme and lipid peroxides. The results indicate an interesting role of the studied agents in burn disease, but still suggestions of treatment of severely burned patients with antioxidants need to be supported by detailed studies.