- Born: 1833
- Died: 1865
- Titles:Shinsengumi Vice Commander, General Secretary
- Japanese: 山南敬助(Yamanami Keisuke or Sannan Keisuke)
Yamanami was Ronin from Sendai han who practiced Onoha Itto Ryu (Menkyo) and Hokushin Itto Ryu (Menkyo). He visited Shieikan dojo first time to match with Kondo Isami. He was defeated and became Kondo's pupil. In 1863, Kondo and other 8 Shieikan members joined the Roshigumi.
Yamanami is believed to involved the assassination of Serizawa Kamo. 1864 January, he captured Futei Roshi at Iwaki Masuya and received prize money from Lord Matsudaira Katamori of Aizu. On the Ikedaya Affair, he stayed in the Mibu Roshigumi headquater.
1865 February 21, Yamanami suddenly ran away from Shinsengumi. He was captured next day and ordered to commit Seppuku along the Shinsengumi Regulations (Kyokuchu Hatto). His grave is in Koen-ji, Kyoto.
- Shinsengumi Zentaishi Tettei Guide (新選組全隊士徹底ガイド) Maeda Masaki
- Shinsengumi Taishi Den (新選組隊士伝) Gakken
- Shinsengumi (新選組) Sekai Bunkasha