William Cunningham was awarded his second dan black belt.
The 11-year-old Mayfield School pupil, who is with Havant karate club, excelled in basics, kata and kumite in front of three Japanese masters at the K2 Leisure Centre, in Crawley.
Havant coach Steve Fife said: ‘William has had a great year being crowned national and four nation champion.
‘Now he is one of the youngest second dan black belts in England.
‘Wiliam has represented England in the JKA World Championships, held in Limerick, Ireland in 2017, gaining more experience at the best karate tournament.
‘His club training is top class and he is also training twice a month at Westminster with the England squad.
‘He trains with the head of the Japan Karate Association in England for extra training. At only 11 years old he has done so much this year and to get his 2nd dan black belt grade has capped a fantastic year.
‘Next year he is back in Serbia for the JKA European Championships to defend his kumite crown.
‘Also he will be going for gold in the nationals and JKA open tournament later next year.’