Why do my eyes burn when I read a book? I know I don't need glasses because I have above average eye sight.

Answer 1

having "above average eyesight" doesnt mean that you dont need glasses. it just means you have good acuity...thats it. a +7.00 hyperope has good acuity too.

go to the eye doctor. you could have farsightedness, convergence problems, accommodation problems, dryness, incomplete lid closure, etc etc etc etc etc etc etc etc. having "good eyesight" is almost never a good indication of whether or not vision correction is needed

Answer 2

probably because when you read you forget to blink, people who spend a lot of time with computers have the same problem. Try to consciously remember to blink while reading.