There are several reasons appearing the phenomenon of burning eyes when go outside. Firstly, you may have spent too much time on computer or reading in your small room, your eyes feel tired and uncomfortable when you see the sun. Secondly, you may have developed a mild inflammation in the eyes. I suggest you use no acyclovir eye drops once two hours, and your handkerchief must be sterilized with boiling water twice a day to avoid repeated infection. Another factor is the outdoor strong sunshine, your eyes will get hurt easily if you don't take some measures to protect them. My advice is eating Le-ding soft capsule because it can supplementary eye nutrition and prevent cataract coming into being.
Ok, from what I know, you are just sensitive to sunshine, which is the strongest light source in the world. A lot of people would get this problem. So, I recommend that you try to get a pair of polarized sunglasses which may fix the problem immediately. Also, you should take care of your eye health by getting a healthy diet, sometimes your symptom is photophobia.
Your eyes must have got the infection. That is the reason for its burning symptom. You should wear the sunglasses to protect your eyes from the uv rays and other bad lights. At the same time, it will reduce the stimulation from the sun. You need to use the eye drops with anti-inflammation to cure the eyes. You could also use the warm compress to make your eyes feel comfortable.