You have responsibility of your visa application to enter Japan.
Please check if you need visa application or not refering to the following website:
https://www.mofa.go.jp/j_info/visit/visa/index.html#section2 In case you need visa application, you need to realize it by yourself at the Japanese Embassy or Consulate-General in your country.
In this case, please answer "Yes" to the question mentioned below "Do you need VISA support documents?"
and send us email about it to ec_gakkai@nta.co.jp as soon as possible.Then we will reply you asking for visa support fee (JPY10,000).
After your payment of this fee, we will issue visa support documents (Letter of Guarantee, Reason for invitation, Schedule of Stay, Conference Program) and send them in pdf file by email so that you could submit them to Japanese Embassy.
Please confirm the other required documents by yourself.
We will accept your request for visa support
by Thursday, July 20.