Willie Peeters (born 26 October 1965) is a Dutch^[1] mixed martial artist.^[2] He competed in the Heavyweight^[3] division.

Peeters started his career in Wrestling at the age of ten, training with famed champion Freddy Winters and winning several junior competitions across Europe. At sixteen, he moved to the Oyama Gym in Amsterdam, where he trained Judo under Chris Dolman and Willem Ruska, as well as Kickboxing under Jan Lomulder, and finally Kyokushin Karate, winning a heavyweight championship. In 1991, after talking about his interest in mixed martial arts, Dolman invited him to his team in Fighting Network RINGS in order to compete in both MMA and professional wrestling in Japan.

Peeters would develop a rivalry with Wataru Sakata in a long series of shootfighting bouts. Peeters defeated Wataru by TKO on their first fight On 16 November 1995, and they went to fight a rematch on 29 June 1996. During the latter, Sakata released late a toehold, injuring Peeters, who retaliated by illegally knocking him out with a close-fisted punch, gaining a red card. Still, Peeters would win by KO due palm strikes. The two met again on 24 August, when Peeters dominated in a grappling contest and defeated Sakata north/south choke. Willie would face Sakata again under different rules in a RINGS Holland event on 8 February 1998, but although Wataru performed dominantly for the first time, he lost a controversial decision, as the Dutch referee invalidated a finishing hold by Sakata while allowing Peeters to throw illegal strikes. Peeters finally lost to Sakata on 27 June by ankle lock.

On 1 July 1999 Peeters fought in Brazilian promotion World Vale Tudo Championship against Antonio Carlos Ribiero. The match, which was lost by Peeters by doctor stoppage, saw copious amounts of blood and Willie biting his opponent, and it was followed by a brawl between their teams.^[4]

• List of male mixed martial artists