Using a numerical model and observations of surface concentration and depositions, the current study provides quantitative assessments of resuspension, transport, and deposition of radio-Cs in eastern Japan in 2013, which was once deposited to the ground surface after the Fukushima nuclear accident. The areal mean resuspension rate of radio-Cs from the ground to the air is estimated as 0.96 % per year, which is equivalent to 1–10 % of the decreasing rate of the ambient gamma dose in Fukushima.