Well preserved fossil plants are newly collected from the Tochikubo Formation (Oxfordian) of the Somanakamaura Group exposed in the northeastern part of Fukushima Prefecture. A total of nine species including three unidentified ones are described herein, among which the following five species are recorded for the first time in this area: Lycopodites sp., Adiantopteris sp., Taeniatus elongatus sp. nov., Taeniopteris somaensis sp. nov., and Pelourdea nipponica sp. nov. In addition, a fragmentary specimen assignable to Neocalamites, the youngest representative of this genus, is obtained. A specimen of the reproductive organ of Williamsonia is newly collected from the Tomizawa Formation. Combined with the previously reported species lists, this study further clarifies the species composition of the Soma Jurassic flora in the Tochikubo and Tomizawa formations, lending considerable support to the representation of one of the important floras of the Ryoseki-type in the Outer Zone of the Japanese Islands.