How do my fiance and I explain to our parents that we are both atheists and do not want to get married in a church by a minister?

If you want to get married, then what's wrong if it happens in a church? I am an atheist too. There doesn't exist "a holy book of atheists" which says that going to church is forbidden. However, if your decision is final, you are stringent about your decisions and you have to express yourself with stringent words. Just Say "NO" mercilessly and repeatedly.

Have a civil service but consider also a church wedding as your gift to them, just to make them happy. Don't you want to give something back?

if you are an atheist ..it means you dont believe in existence of God...if its the case thn you should nt be having any problem the way you get married .....do whatever your parents say..........................................and yes if you feel anguish whn somon tlks abt God it means tht u r not an atheist as you belief in his faith and existence thts why you are angry with him........thn you are only angry with him....if you believe in science then church marriage not important but whats the problem if your parents wants that way

Simply tell them what you feel.  It's surely shows a crumbling of the old belief systems followed unquestionably by zillions on this earth.  Marriage is an institution which of course generates lots of $, think about turning the table in your favor and for your betterment.  It's interesting to see people who overtly talk about change  and do what  they think needs to be changed.

Being an atheist doesn't preclude your getting married in a church. You might have a personal problem with feelings of hypocracy but getting married is a civil matter. Where you do it makes no difference to the outcome. The vast majority of church weddings are entered into by people who have little or no faith and who will possibly never enter a church again excepting it comes time to christen their children or bury their parents perhaps.

Dad, Mom we don't want to have a pompous grand marriage but just a simple court marriage and a small reception with close family and friends. Try saying about saving money for charity or future.

Marrying in a church can be considered a cultural practice, even though it has a christian priming. One is either an atheist, or not. Marrying in a church should not hamper one's reason powered belief system. Also the institution of marriage has a religious realm to it. Hardcore atheists should not necessarily buy the concept of conventional marriage. Evolution has a different approach towards human bonding patterns. And finally to answer your question, don't bother with the exercise. Getting married in a church should not matter, if you truly do have an understanding of the "Science of Reason."

I'm going to provide an alternate view that has not yet been spoken for: You certainly can view the wedding as for your own benefit, but you might also view the wedding as for all the people in your life (parents included!) who have brought you to this point. From this perspective it would be important to make sure your wedding at least partially meets their expectations and that might mean having your ceremony in a church.

I agree with Andy McFarland.  You don't ask, and you don't explain.  That makes it more of an issue than it really is.  If you're old enough (and mature enough) to get married, you don't seek approval from Mum and Dad.  I understand the wish for approval, but remember, if you ask a question, there's a 50-50 chance that the answer is "No," so you're kind of backing them into a corner as well.  Don't even discuss it unless they ask, and if they do ask, state the facts and let them know the decision is made and is not open for debate.  I know this sounds really simplistic, but remember, this is not a one-off -- if you have children, it will come up again with the baptism issue.  Best to be honest and avoid years of pretending, lying, skirting the issue.