is a Japanese footballer who plays as a right winger for Kamatamare Sanuki.
On 13 August 2013, Miyaichi was registered as a Specially Designated Player.
Tsuyoshi Miyaichi was signed by Shonan Bellmare in 2014. He made his league debut against Tokyo Verdy on 31 May 2014. On 6 December 2018, it was announced that Shonan Bellmare would not be renewing his contract.
Miyaichi was loaned to Mito Hollyhock in 2015. He made his league debut against Roasso Kumamoto on 8 March 2015.
For 2016 he was out on loan to J3 team Gainare Tottori.
On 29 June 2017, he was announced at MIO Biwako Shiga.
In 2018, Miyaichi moved on loan to Grulla Morioka. He made his league debut against Gamba Osaka U-23 on 11 March 2018. Miyaichi scored his first league goal against Cerezo Osaka U-23 on 7 July 2018, scoring in the 13th minute.
On 8 January 2019, Miyaichi was announced at Iwate Grulla Morioka. He made his league debut against Roasso Kumamoto on 31 March 2019. Miyaichi scored his first league goal against Azul Claro Numazu on 9 June 2019, scoring in the 36th minute. On 15 December 2020, Miyaichi's contract was renewed and he was diagnosed with Osgood syndrome.
Miyaichi is the younger brother of Ryo Miyaichi.
Updated to 2 April 2023.