[en] It is necessary to develop the rapid and on-site detection method of radiocesium (Cs) in soil in order to carry out the decontamination of radioactive materials efficiently. The most common analyzer for the quantitative analysis of radio-Cs is the gamma ray spectrometer with the semiconductor Germanium (Ge) detector to evaluate the concentrations of radio-Cs in soil. However, this equipment is large-size, and demand liquid nitrogen cooling. So it is not suitable for on-site measurements. Here we show that there is a highly significant correlation between the analytical values of the portable NaI(Tl) spectrometer and that of the Ge spectrometer. This indicates that the portable spectrometer enable us to determine the quantity of the concentration of radio-Cs in soil on site. Then, we also measured the contaminant soil by three kind of handy survey meters (NaI(Tl) detector, GM, and CsI(Tl) detector) under the fixed condition. These measurement values have good correlations with the concentration of radio-Cs. It is suggested that the radio-Cs concentrations are estimated by the handy instruments under the controlled measurement condition. (author)