Can I trade in my finance car?

I have 2013 honda civic but I don't like it at all i just bought it since it was the only option as a first time buyer have me 4.9% APR no one else gave me these low APR. But now I want the 2014 kia optima i currently owe 18.290 won't finish paying it till nov/2018 which is long time don't want to wait can i trade it in for new car? How does it work? I don't have a down payment for new car?

Not really, you will not get a such a cheap APR on a KIA, your not a 10 year old anymore, you can't just change your mind every 5 minutes not when it come to loans and finance. You must grow up now, you must think before you sign a contract for "5" long years.

Talk to your Kia dealer. It sounds like you would be so upside down (trade in not worth anywhere what you owe on your Honda) that no one would finance the deal. Obviously if your credit score has not increased any, no one would loan you the money at a decent rate.