|Full name||Jun Kato|
|Born||25 October 1980|
|Highest ranking||No. 367 (28 July 2003)|
|Highest ranking||No. 121 (3 May 2004)|
|Grand Slam Doubles results|
|French Open||1R (2004)|
Jun Kato (加藤 純 Katō Jun, born 25 October 1980) is a former professional tennis player from Japan.
Kato was based in Switzerland from an early age. During his junior career he was friends with Roger Federer and partnered with him in several doubles tournaments. He beat Federer in a national under-12s final.
Turning professional in 1998, Kato made his first appearance in an ATP Tour tournament that year, the doubles at the Swiss Open Gstaad with Marco Chiudinelli. He was twice given a wildcard entry into the men's doubles draw at the Japan Open, the first in 2002, when partnered with Gouichi Motomura to reach the quarter-finals. On the other occasion, in 2003, he and Satoshi Iwabuchi upset the top seeded pairing of Wayne Arthurs and Paul Hanley in the first round, en route to the semi-finals.
Kato represented the Japan Davis Cup team in 2003, for a tie against India in New Delhi. He played the doubles rubber with Thomas Shimada, which they lost to Mahesh Bhupathi and Leander Paes. In the reverse singles he was beaten by Rohan Bopanna.
|1.||2003||Togliatti, Russia||Hard||Alexander Peya|| Rodolphe Cadart
|2.||2003||Valladolid, Spain||Hard||Łukasz Kubot|| Philipp Mukhometov
|4–6, 6–0, 6–1|
- Wehrle, Michael (4 November 2011). "Jugendfreunde erinnern sich an Roger Federer". Limmattaler Zeitung (in German). Retrieved 15 March 2016.
- "ITF Tennis - Juniors - Player Profile - Kato, Jun (JPN)". International Tennis Federation. Retrieved 15 March 2016.
- Bowers, Chris (2 May 2011). Roger Federer: The Greatest. John Blake Publishing. ISBN 9781843585923.
- "Japan Open". St. Louis Post-Dispatch. 2 October 2003. p. 12. Retrieved 15 March 2016.
- "ITF Tennis - Pro Circuit - Togliatti Challenger - 14 July - 20 July 2003". International Tennis Federation. Retrieved 15 March 2016.
- "ITF Tennis - Pro Circuit - Valladolid Challenger - 21 July - 27 July 2003". International Tennis Federation. Retrieved 15 March 2016.
- Srinivasan, Kamesh (9 February 2003). "Leander-Mahesh duo makes it a no contest". The Hindu. Retrieved 15 March 2016.
- "Bopanna wraps it up for India". The Telegraph. 10 February 2003. Retrieved 15 March 2016.
- Bricker, Charles (27 May 2004). "U.s. Is French Toast". Sun-Sentinel. Retrieved 15 March 2016.