The Tokyo Toy Show is Japan’s biggest show for the toy trade. While the first two days (Thursday and Friday) are trade only days, the event is open to the public on the weekend. Note that the doors close slightly earlier (at 4pm) on Sunday.
Don’t expect it to be just a stuffy trade show. There will be a stage with entertainment for the kids – including appearances from various characters – as well as a “kid’s park” with toys (of course) and activities.
The event takes place at the Tokyo Big Sight site.