As the sum of each row is the same, and the sum of the four rows is equal to the sum of 1 + ... + 16, the sum of each row is a quarter of 1 + ... + 16. Hence the answer is 34.
34 can be divided into 2 equal groups, that is 17, 17. So think about the combination of 1,16;2,15;3,14;4,13;......
Then use 2 groups to fill each row and column........