A professional MMA competitor since 1996, he was a longtime veteran of PRIDE and Pancrase and has also competed in other mixed martial arts promotions such as K-1 Hero's, Cage Rage, the SFL, Vale Tudo Japan, UFC, DREAM, and DEEP.
Often undersized and a huge fan favorite in Japan, Minowa earned his nickname "The Giant Killer" by participating in many openweight contests, often submitting much larger opponents.
Minowa made his PRIDE Fighting Championships debut against future UFC Light Heavyweight Champion Quinton "Rampage" Jackson.
Minowa was known in PRIDE for his entertaining entrances and sporting of the Japanese flag as a cape as well as his aggressive, high-risk style of fighting which has seen him employ flying dropkicks amongst other pro-wrestling derived maneuvers.
It was also during his career with PRIDE that he continued to cement his legacy in taking on fighters that were much bigger than himself, winning most of the resultant freak show fights and earning the nickname "The Giant Killer".
He participated in PRIDE's first 185 lb tournament where he won over Phil Baroni, but went on to lose in the second round to former UFC Middleweight Champion Murilo Bustamante.
On December 31, 2005, Minowa fought the legendary Kazushi Sakuraba, in which he almost landed a kneebar and then a heel hook, but was caught with a Kimura lock and defeated at nine minutes into the first round.
However, he then rebounded with wins over Park Hyun Kab, Eric "Butterbean" Esch, and American professional wrestler Mike Plotcheck.
The Japanese performed well, circling the less mobile Brazilian and at one point throwing him with seoi nage, but Zulu eventually caught and smothered him, finishing him with ground and pound.
2009 Minowa squared off with Cameroonian fighter Rameau Thierry Sokoudjou in the finals of the DREAM Super Hulk tournament.
In the third round Minowa and Sokodjou both received two yellow cards (10% purse deduction for one) for inactivity 3 minutes into the round, but with 90 seconds left Minowa sprang forward and connected against Sokoudjou's jaw with a left hook, dropping him to the ground for the TKO victory and winning the Super Hulk Tournament.
Then for DREAM 16, Minowa was scheduled to fight James Thompson but three days before the event, had his opponent switched to Satoshi Ishii and he lost by unanimous decision.