Can I marry a Japanese when I travel to Japan?

You can't get married here on a tourist visa. You can only apply to Japan after you get a marriage certificate in China. If the other person is a permanent resident, your friend came to Japan on the visa of a permanent resident spouse. The waiting time for a visa is 2 to 3 months. After that, you will be allowed to stay for one year, then you will be allowed to renew your contract directly in Japan, then you will be allowed to stay for three years and then you will be allowed to apply for Japanese citizenship for five years. If you don't want Japanese nationality, you can only renew it for seven years to 10.