The issuing of transcripts and diplomas is handled by the office of your respective graduate school. Please check the contact information for your graduate school and contact them directly with any questions.
For contact information, please click here

http://www.hiroshima-u.ac.jp/category_view.php?category_id=14&template_id=8&lang=en

(1) If applying in Japan:
The Metropolitan Police Department or Prefectural Police Headquarters issues this certificate. As each Prefectural Police Headquarters requires different paperwork, please ask for details at the police headquarters where you registered your residence or you received your Alien Registration Card. The process takes about 1~2 weeks to complete and you must apply for the certificate in person.
For details, please contact Hiroshima Police Headquarters at 082-228-0110.

(2) If applying from outside of Japan:
Certificate of Innocence is issued by diplomatic missions abroad. Please submit all the necessary paperwork and be aware that the process takes about 3 months to complete. For more details please see: 　

http://www.mofa.go.jp/mofaj/toko/todoke/shomei/index.html#3 (Japanese Only)

Hiroshima University-issued documents and certificates such as diplomas, transcripts, certificates of health, etc, may not be accepted as official documents in your home country. In that case, you will need a Ministry of Foreign Affairs Authentication Certificate; therefore, we recommend that you check with your Embassy about whether your country will accept the diploma before you leave.
Documents for authentication are limited to those documents that have been issued within the last 3 months. Although applying for authentication must be done in person as a general rule, you can have the procedure done by proxy, however you must be sure to submit the appropriate forms. When you apply for authentication, you must show either official document or card with your picture on it such as a passport, driver's license, or Alien Registration Card. If you do not have any official documents or cards with your picture, please show your health insurance card. For more details, please inquire at the diplomatic mission of your country in Japan.

The Ministry of Foreign Affairs will not accept authentication applications from abroad. For those living abroad, we ask that you apply for authentication through a Japanese proxy.

For more details, please see:

http://www.mofa.go.jp/mofaj/toko/todoke/shomei/index.html#3(Japanese Only)