Here is why May 9 is recognized as 'Goku Day' in Japan Posted by Justin 'AdaptiveTrigger' Gordon • May 9, 2021 at 10:24 a.m. PDT • Comments: 12 Earlier today, Toei Animation announced a new Dragon Ball Super movie slated for 2022 — though we already knew that since it was accidentally leaked ahead of time. This announcement came today for the purpose of commemorating "Goku Day." But what is "Goku Day" exactly? The Japan Anniversary Association has been officially recognizing May 9 as "Goku Day" in celebration of the Dragon Ball series since 2015. Apparently the main reason for this is because of a pun with Japanese pronunciation. There's actually a very simple reason why May 9 is Goku Day. It's simply because it's the ninth day of the fifth month of any given year.