Visa is required for citizens of Japan to visit Vietnam. Japan nationals may have 2 options:
Visit Vietnam embassy in Japan
or apply for a visa on arrival
to Vietnam from Japan online.
Japan citizens may apply for both tourist and business visa to Vietnam for the stay of 1 to 6 months from Japan.
Please check this link for visa fee
for Japan citizens.
All the information for getting a visa from Vietnam embassy in Japan can be found here: updating...