Amounts of waste impregnated wood will increase significantly in the future years. Ordinary burning and land fielding is not allowed due to high biocide contents. Possibility of reuse of waste CCA treated wood was elucidated herein. Using method of X-ray fluorescence spectroscopy (XRF) was confirmed, that the major part of the Cr and As compounds remained in the 50 years old CCA treated timber, on the other hand, the major part of copper salts leached from wood. Laboratory leaching confirmed that after such extensive period, the mayor part of biocides remained fixed and did not leach from wood. In addition, mini block method proved that CCA treated wood, that was in use for 50 years, is still resistant against brown rot fungi and we could reuse it.