Abstract
The diatom flora from paddy fields in northern Laos was studied. Soil samples were collected from a depth of 0-1 cm in 6 paddy fields in the Nam Ben River basin in October,2003, and 8 paddies in Ay village in September,2004. In total,104 diatom taxa belonging to 28 genera were identified. They are illustrated together with 11 unidentified diatom taxa. The dominant genera were Nitzschia and Pinnularia. Navicula pygmaeformis H. Kobayasi is transferred to a taxonomically more suitable genus, as Fallacia pygmaeformis (H. Kobayasi) Y. Fujita et Ohtsuka comb. nov.
