At the age of 18 whilst attending To-Yo University Manzo Iwata began training in karate-do directly under Grandmaster Kenwa Mabuni, the founder of the Shito-ryu system. Mabuni Sensei also taught Manzo Iwata Bojutsu (6ft staff) and encouraged him to learn Jojutsu (a shorter staff) from his friend Master Seiko Fujita.

In 1943, Manzo Iwata was honoured by receiving the ‘Shihan’ (master/teacher) diploma of Daienryu Jojutsu from Master Fujita who later revealed he was the 14th generation Master of the Kogaryu Ninjitsu system of martial arts. After graduating from To-Yo University Manzo Iwata received the ‘Shihan’ of Shito-ryu Karate-do directly from Master Kenwa Mabuni.

Master Iwata continued promoting the Shito-Ryu system around the world and remained faithful to Mabuni Sensei's teachings especially with regard to kata and bunkai kumite. Iwata Sensei died June 4th 1993, but his memory and legacy live on through his students such as his son Genzo Iwata, Shito-Kai Honbu Dojo Chief Instructor and Kunio Murayama Sensei among others.