Atsushi Oka (岡 篤志, Oka Atsushi, born 3 September 1995) is a Japanese professional cyclist, who currently rides for UCI Continental team JCL Team Ukyo.

After three years at Japanese UCI Continental team Utsunomiya Blitzen, Oka signed with French UCI ProTeam Nippo–Delko–One Provence in 2020, joining compatriots Fumiyuki Beppu, Masahiro Ishigami, and Hideto Nakane.

[2] Oka made his debut for the team at the 2020 La Tropicale Amissa Bongo.

[7] On 28 April 2021, Oka received a four-month suspension from the UCI after an anti-doping control test came back positive for acetazolamide, a drug banned by WADA that is often used to treat altitude sickness.

Given the retroactive suspension from the date of the positive on 13 December 2020, Oka was eligible to race again on 24 May 2021.