Abstract: DIFFERENT DISCUSSION ON THE INFLUENCE OF RADIOACTIVE SOURCE DECAY ON ISOTOPE INSTRUMENTAL MEASURING ERRORSong Weidong(Institute of Isotope, Henan Academy of Sciences, Zhengzou 450052)ABSTRACTThe influence of radioactive source decay on isotope instrumental measuring error is also analyzed.Our conclusion is opposite to the published article written by Min Hainan et al. The mistakes of the original article is given here passing through a practical example.Key words measuring error radioactive soure decay isotope instrument logarithmic ratemeter linear ratemeter