Yes. You can claim him if he satisfies all the dependency requirements are met. His income is not an issue. He doesn't have to live with you. However, you need to provide half of his support.
The 4 tests that will qualify a relative as a dependent are:
· Qualifying Child: They are not the “qualifying child” of another taxpayer or your “qualifying child”.
· Gross Income: The dependent being claimed earns less than $4,050 in 2017 ($4,050 in 2016).
· Total Support: You provide more than half of the total support for the year.
· Member of Household or Relationship: The person (a friend, girlfriend, non-blood relative) must live with you all year as a member of your household.
Please feel free to post any additional details or questions in the comment section.