Abstract: The chemical yields of overall process for analyzing 238 Pu in more than 600 soil samples are determined by using 236 Pu as a yield tracer. The values of chemical yield appear normal distribution. The most probable yield value is 0.48, standard deviation is 0.20. Great errors will be engendered for radiochemical analysis of plutonium isotopes if corrections of measured results only based on predeterncined chemical yield obtained by tracing test as a fixed corrected factor of 0.70 and not using chemical yield obtained tracer as dynamic corrected factor.