Meeting my girlfriends parents

I will meet my girlfriends parents and I would like to use the most proper Japanese in this situation to say that I am dating their daughter (or ask if I can date their daughter, eventhough we already are). I speak fairly good Japanese, but I don't know culturally what is expected in this situation.

I post this question in the language section, because I'd especially like to know if there is usual expressions, things to say or not to say, and what is the correct way to say it. (like how should I be addressing to them, should I use okaasan/otosan...etc)

Thanks in advance!

Is this a serious question? Just ask your girlfriend! Contrary to a common misconception, Japanese people are not all the same, she is the best position to tell you how to behave with her parents.

Yes, it is serious. I didn't realize I was on a relationship advice forum :)

Of course I have talked with her... but I'd still like to know what is the "traditional way" behavior and language. Maybe i didn't make it clear but this is a cultural level question, I don't actually need advice on my particular case.

See in the US, even though its less and less common, I'd say traditionally you ask the father one on one, expressing your felling for her daughter blabalbla... I'm sure there must be an equivalent in Japan, and I 'd like to know how it is going, if anyone knows.. ?

First of all, you can contact the admin to get this thread moved to the language section, if you wish.

I post this question in the language section, because I'd especially like to know if there is usual expressions, things to say or not to say, and what is the correct way to say it.

Well, that's pretty much a relationship/custom question, and like Firas I don't see the point.

(like how should I be addressing to them, should I use okaasan/otosan...etc)

This question has been answered many times, and I can't understand why your Japanese girlfriend can't answer that, but if you're speaking in your native language, you should follow that custom. For example, if you are to speak in English, you should call them "Mr/Mrs. (family name)" unless you are advised otherwise from the parents themselves.

If you are speaking in Japanese, you can get away without addressing them at all. But if you must, you can call them "(girlfriend's first name) no otousan/okaasan" just as you would for any friend's parents.

Greating them with a neat "hajimemashite, (your family name) desu." would be a typical proper greeting for any occasion. And then you can say "ojamashimasu" as you are entering their home, and then "shitsurei shimasu" as you are stepping on their floor or entering a different room. I don't think you have to blah blah or whatever unless you are asked to.

Sorry for my previous typo.

Incorrect:
But if you must, you can call them "(girlfriend's first name) no otousan/okaasan" just as you would for any friend's parents.

Correct:
But if you must, you can call them "(girlfriend's first name)-san no otousan/okaasan" just as you would for any friend's parents.

Just on a cultural note: meeting the parents of your girl friend is a rather big thing in Japan, and it could be a bit uncomfortable (at least it was for me). For instance I wore a suit and we met in a restaurant, neutral territory so to speak, as they first wanted to see what their daughter had caught as obviously they weren't too happy with me :-)
Ask your girlfriend for advice on what to bring as gifts.

In my case, the asking-for-permission "I promise to take care of your daughter, etc. etc" speech was before our marriage, that one was far more tough as I had to sit in seiza for quite a while and that made it even more difficult. As you can guess, my parents in law are from the countryside ;-)

For instance I wore a suit and we met in a restaurant

As it is in any country, it depends on what the occasion is, and also what the parents are accustomed to.

Wearing a suit and meeting for dinner already means that it's going to be very proper. One might expext that this is heading for marriage or something very serious, and suits usually show how reliable a man can be.

On the other hand, some people prefer it to be more casual on the first meeting so that everyone could be relaxed. Casual occasions are convenient in the sense that it makes everybody feel that the members there are ordinary people after all.

You're absolutely correct Uco-san in your explanations; I think the important thing is to make sure that both parties have the same expectations of the meeting and this is where your girlfriend can help so everybody agrees on this before the meeting and no hurried explanations are needed after the meeting :-)

the OP does not understand that the marriage with a foreigner,itself, is "out of tradition".
since your behaviors are "out of tradition", why do you try to imitate the traditions ?
it is extremely important that "礼を失しない", "treat them politely (respectfully or properly)". they are not your friends, not your parents. but they are not third persons (non-related persons).
if you are an US citizen, use the words as if you speak to US president.
it is not so difficult, if you are well educated.