Most historians agree that the people of Roanoke Island were absorbed by a nearby tribe. There were reports of "white Indians" following their disappearance. Nothing is conclusive, but that's the general belief. Hope this helps!
Check out a few versions of this question asked recently (in fact I just added it to the FAQ).
What happened to the "Lost Colony" of Roanoke?
What is known about the settlers of the Lost Colony of Roanoke?