Marriage certificate issued by home country

I am changing my residence in japan and one step on the government site of justice https://www.moj.go.jp/isa/applications/status/spouseorchildofjapanese0... says that I need my marriage certificate issued by my country of nationality. I was recently married in japan so I have juri shomeisho but i am unable to get my marriage certificate from my home country within the timeframe. However, the US embassy in Japan site says that juri shomeisho would be the only available “proof” of marriage if any country government were to ask, so would just my juri shoumseisho suffice?

As far as I know, yes, what the US Embassy said is correct - since you got married in Japan (under the Japanese law), and that marriage is automatically recognized by the US authorities (though I don’t know about the individual States), they do not require that you report the marriage to the US authorities, thus they do not issue any certificate.

This fact should be known to the immigration authorities, but if they insist on it, you might have to write up a letter explaining the situation (that is, that the US does not issue any certificate on Japan marriages).

Your marriage should be registered into your Japanese spouse’s “koseki” (family register) soon, so you should obtain an official duplicate of “koseki” as well.

Best wishes, and congratulations on your wedding :)

if you google it, there are many websites (in Japanese) which describe the above point, written by professionals.
please ask your spouse's help. it is essential.

if you are currently in Japan, you need to apply immigration the change of the resident status, instead of certificate of eligibility of the spouse visa of Japanese nationals.