Visa under maiden name

Hi! I would just like to ask about the validity of my japan visa..
I had my passport renewed due to change status (married) but my multiple japan visa is attached in my old passport under my maided name and will expire on year 2020

Do I still need to apply for a new visa? Or can I use my old visa even if my new passport has different surname? Do i have to show my marriage certificate in the immigration?

http://www.ph.emb-japan.go.jp/itpr_en/00_000035.html

Nothing about my visa under my maiden name but passport is under my married name stated on the link above..

I think the other poster was implying that you should also look at the part of the Embassy's link where it says "For Inquiries". Frankly, I don't understand why you're asking anonymous internet users like us instead of asking the Japanese Embassy in your country.

It depends where you live. Some countries taking a husband's (or wife's) name is not actually a legal requirement, but a social convention, even though the new name is used as a legal name (and therefore technically you can use both). Getting married doesn't necessarily result in a change in your passport for example.
Other places, you are forced to give up your name.
So, to answer your question you have to work out what your legal name/s are and then check the notification requirements for your Japan travel documentation.

This is an old post but for the sake of others who will have same situation as of 2018, you can use your visa in the maiden name. Just attached your old passport with the visa to the new passport with married surname. Pls also bring marriage contract and old ID in maiden name just incase you will be asked by the immigration.