If I claim my son who is in the military what does he need to do on is taxes?

[anewel2007]

He lived with us until Oct. of 2016 and has been in training school since.

[DanielV01]

He will file a dependent return.  What this means is that, since you are claiming his exemption, he will not be able to.  If he made $6300 or less, this will have no impact on his return.  If he made more, it will affect him, but not likely as much as the benefit you receive by claiming him.

Remember, though, that for him to qualify as your dependent, he either was under 19 years of age on December 31, 2016, under 24 and still a student, or made less than $4050 (which is the exemption amount) if he was at least 19 and not a student.  (If he graduated from high school, he was a student this year).