Cyber3 Conference
http://www.npr-event.jp/cyber3

Cyber Tech Conference
http://tokyo.cybertechconference.com

Pac-Sec
https://pacsec.jp

Code Blue
https://codeblue.jp

Cyber Secure Car
https://www.cybersecurecar.com/japan

MPower Cybersecurity Summit
http://mcafeempower.com

Risk Control : Security & Safety Trade Expo
http://www.kikikanri.biz

Global Station for Big Data and Cybersecurity (Hokkaido)
https://gi-core.oia.hokudai.ac.jp/gsb

IWSEC  (Different city in Japan each year)
International Workshop on Security
http://www.iwsec.org/

other links

https://www.csis.org/regions/asia/japan

https://cybersecurityventures.com/

Tokyo Crypto-Park
https://tokyocryptoday.github.io/index.html