It is well known that cigarette tobaccos contain naturally occurring radioactive nuclides such as Pb-210 and Po-210. In many countries, the radioactivity of tobaccos has been measured to estimate the effective dose from smoking inhalation. The present study covered 24 cigarette brands including the top 20 of sales in Japan between April 2008 and March 2009. The activity concentrations of Pb-210 were measured by gamma-ray spectrometry, and then those of its progeny (Po-210) were evaluated assuming the radioactive equilibrium between the two nuclides. Their concentrations were in the range of 214 mBq cigarette(1) with an arithmetic mean of 83 mBq cigarette(1). The annual committed effective doses were also calculated, based on the scenario that a smoker consumes 20 cigarettes a day. The average doses from Pb-210 and Po-210 inhalations were 229 and 6827 Sv y(1), respectively.