The movie stars admit it happens all the time - and it really baffles them.
In a joint interview for Empire magazine, Elijah recalled one fan encounter and said, "Once I was in an elevator... just me and one other person, and I could feel them looking at me intently. Just before the door opened, he got up the courage, pointed at me and said, 'Harry Potter!' I said, 'No!' and I walked away."
"Harry Potter" actor Daniel can't understand why they are frequently mixed up because he doesn't think they look alike at all.
"Though we're both short, pale, blue-eyed and brown-haired, I would say that we don't exactly look alike," the Brit shared. "But the idea of us is exactly the same. When people say to me 'Lord of the Rings!' I literally just say, 'Nope.' "
Daniel even once made a statement with an autograph signing after he was mistaken for Elijah.
He added, "I was once on a red carpet in Japan and a photo of you (Wood) was thrust at me. My first instinct was to say, 'Oh, I'm not... So I can't...' but I thought the language barrier would be too much."
"So the quickest way to deal with it was just to write, 'I am not Elijah Wood, (signed) Daniel Radcliffe,' and then hope somebody translated that for him later."
Although the celebrity confusion can be a little annoying for the pair, Elijah previously admitted he finds it "amusing" when he's mistaken for Daniel.
He said, "It's really common. I ran into somebody the other day and they said, 'I loved you in 'Swiss Army Man'. I was like, 'Oh, there we go again!' I actually find it really amusing."