It is true that washing eyes with cold water can reduce dark circle of eyes. Dark circle of eyes is caused by an impairment of blood circulation in your eyes. Cold water applied to the eyes is a good way for you to relieve fatigue and reduce dark circle of eyes. But if you really want to reduce dark circle of eyes and want to have a pair of attractive eyes, washing eyes with cold water is not enough. You should also do the following things: firstly, you should go to bed as early as you can. Secondly, it is better for you to cover your eyes with wet towel regularly, which will make your eyes feel better. Thirdly, do some massage for your eyes and use some brands of eye cream. If you keep doing these things, I believe you will own charming eyes without dark circle of eyes one day.