Suzuki Bunji, Nishio Suehiro, Akamatsu Katsumaro, Shimanaka Yuzō and Kagawa Toyohiko were Central Committee members of the party.
[8] In March 1927 the General Federation of Japanese Peasant Unions was formed as the agrarian wing of the party.
(Japanese: Nihon Nomin Kumiai Sodomei) was a farmers' organization in Japan.
It changed its name to Social Democratic Women's League in July 1928.
[10] Regarding the Chinese question, the party opposed the policies of the Japanese government, demanding a recognition of the Nanking government and encouragement of the Three Principles of Sun Yat-sen.[11] In May 1927 the Social Democratic Party sent Miyazaki Ryusuke and Matsuoka Komakichi to Shanghai, where they met with Chiang Kai-shek.