Full Metal Dojo Kongsrichai made his mixed martial arts debut for the Thai promotion Full Metal Dojo. On 23 August 2014, Kritsada Kongsrichai made his debut at
Full Metal Dojo 2: Protect Your Neck, where he lost to Kichong Tran by second-round submission via rear-naked choke. He would pick up his first professional victory on 22 November 2014 at ''Full Metal Dojo 3: No Sleep 'Til Bangkok'' with a first-round submission of Manachai Promsawad via rear-naked choke. On 6 March 2015, he lost to Caleb Lally by TKO at
Sena Combat: Pattaya Fight Night. On 22 August 2015, he defeated Detchadin Sorsirisuphathin by TKO at
Full Metal Dojo 6: For Those About to Rock... to capture the vacant FMD Bantamweight Championship. Kongsrichai would then defeat Pakorn Isarat by submission via rear-naked choke in the first round at
Full Metal Dojo 10: To Live and Die in Bangkok on 19 March 2016.
ONE Championship With his success and title win on Full Metal Dojo, Kongsrichai was eventually contacted and signed by
ONE Championship. Kritsada Kongsrichai made his ONE Championship debut on 27 May 2016 at
ONE Championship: Kingdom of Champions, where he defeated Kev Hemmorlor by first-round TKO. His next fight saw him facing future
ONE Strawweight World Champion Joshua Pacio at
ONE Championship: Heroes of the World on 13 August 2016. Kongsrichai lost the fight by submission via rear-naked choke. On 11 March 2017, Kongsrichai faced Adrian Mattheis at
ONE Championship: Warrior Kingdom, where he won via first-round TKO after dominating with his wrestling-based grappling. On 9 December 2017, Kongsrichai defeated Rabin Catalan by first-round TKO at
ONE Championship: Warriors of the World. Next, Kongsrichai was matched up with Robin Catalan, Rabin Catalan's brother. On 24 March 2018, the two faced off at
ONE Championship: Iron Will. Kritsada Kongsrichai appeared to win the fight by TKO after executing a suplex on Catalan. However, after the fight, reviews determined that the suplex was illegal and the result was reversed to a disqualification loss for Kongsrichai. On 29 June 2018, Kritsada Kongsrichai faced Jeremy Miado at
ONE Championship: Spirit of a Warrior. After the fight went the distance for three rounds, Kongsrichai was awarded the unanimous decision victory.
Post-ONE After over a year away from mixed martial arts action, Kongsrichai was scheduled to return to face Kosuke Terashima at
DEEP 94 Impact on 1 March 2020. He lost by second-round TKO via submission to strikes. Kongsrichai was scheduled to return to mixed martial arts against John Shink at
Fairtex Fight: Descendants of the Empire II, to be held in
Lumpinee Stadium, on 12 March 2022. He lost by first-round knockout. He faced Kim Kyu Sung at Fairtex Fight: Domination on 11 June 2022. Kongsrichai lost by second-round technical knockout. ==Fighting style==