What are the best and affordable restaurants in Seoul?

Saladian is a restaurant that specializes in salad dishes, serves vegetarian food, and is recommended by the Seoul Government. The name is a newly-coined word that means a person who loves salad. The portion size of their salads makes for a filling meal, and you can add more toppings and other condiments as well. The restaurant chooses the freshest and healthiest ingredients, and they use pasta made of 100% semolina. Their pasta with olive oil is the most popular item besides the salads.

Take the subway line number 2 from Samsung Station (Connected to  Coex building) to Yeoksam. It's 2 stations away toward the station in Gangnam. Take the exit number 6. Walk toward Cha Hospital for about 150 meters. There is a restaurant called Pyung Ga Ok. Try On Ban (11,000 Won~12,000 Won)" or Naeng Myun (11,000 Won). It's dumpling ("Mandoo") is very good, too. Price per dish is around 10,000 Won (about 9 USD). Very good food, highly recommended.

After Pyung Ga Ok, walk to the Gangnam Station (about 7-minute walk) and walk around. There are nice restaurants all over. Be brave. Ask around. You will find lots of young people willing to help you. Enjoy Seoul! - HK 

The COEX Mall will not be cheap but if you go to the central areas of Seoul there are a lot of nice and affordable restaurants more available for you. I think that this one is a good list to start with:

http://www.trazy.com/theme/korean_restaurants

You *have* to try Sanchon, Buddhist temple Korean food - full of roots and vegetables over many delicious courses. It's authentic, delicious, healthy, and won't break the bank (especially if you go during lunch).You can find information about it here: http://www.tripadvisor.com/Restaurant_Review-g294197-d802826-Reviews-Sanchon-Seoul.html 

You must also go to Koong, which serves North Korean style dumplings and dumpling soup. Dumpling soup is my favorite food, and I literally dream about this place: http://www.seoulfood.org/2011/koong-mandu-soup/

If you want delicious Korean - Italian fusion, try Tasting Room, in Cheongdam, just a few minutes away by taxi. It's delicious, trendy, and for upscale dining, not too pricey. I've seen one or two celebrities there too, if that's your thing. http://www.tastingroom.co.kr/

My favorite neighborhood is Samcheong-dong, where you can walk along the main street, do some shopping, check out traditional architecture, and get great food at every corner. http://www.tripadvisor.com/Attraction_Review-g294197-d6656879-Reviews-Samcheongdong_gil_Road-Seoul.html

Download the YAP app. Go to Ho Lee Chow by the Hamilton HotelOrder one entree. Get a free Sheshuan Chicken with yap. Bon appetite!

Ankara Palace for Turkish lunch buffet for 13 or 15,000 won.??

Hi.  COEX Mall (Gangnam area of Seoul) just recently re-opened a couple of months ago after a total makeover.  For breakfast foods, Butterfinger Pancakes is popular, especially for their french toast. Burger B Kitchen & Bar has a fun menu and you can get burgers, bbq, sandwiches, salads. Mad For Garlic for Italian fine dining.  These are a few I'm familiar with. All of these are within walking distance of COEX. www.koreaye.com has a list of Restaurants and lots of good tips for visitors.  Enjoy your visit and let me know if I can help with any other info. Oh, and I'm originally from North Carolina :)

there's not delicious food near COEX Intercontinental. ...so i think recommend go to Gangnam for you!

There is a a cheap restaurant named Rolled In Heaven.