Paddy soil samples were collected at the regions of Kitakyushushi-kinko, Buzen-tobu and Buzen-seibu situated in the northeastern part of Fukuoka prefecture, Kyushu, and analyzed for the layer-silicate minerals of the <2μm clay fraction. Most of the soils were characterized by the low clay content (less than 300gkg^<-1>). Principal clay mineral was kaolin mineral followed by micas, vermiculite and 2 : 1mineral-chlorite intergrade. Soil samples were classified based on the similarity of the clay mineralogical composition and 99 soils were classified into 10 groups. Distribution of the mineralogical groups was affected by the geological and topographical characteristics in the regions. The rice yields of both 1985 and 1990 of the Buzen-tobu region were attempted to be correlated with the mineralogical groups. The average of the rice yields of all the groups, however, ranged between 4.6 and 4.9 Mg ha^<-1> in both years and there was observed essentially no difference between the goups.
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