Sean Arnold (born 30 January 1941 in Gloucestershire) is an English actor.

He is best known for his roles as Mr. Llewelyn in Grange Hill in the 1970s and 1980s, and as Barney Crozier in the 1980s BBC television series Bergerac. He played Commander Telson in the 1981 BBC Radio 4 science fiction serial Earthsearch and the 1982 sequel Earthsearch II, and later appeared as the Chief Constable in Merseybeat. He also played Dr. Harry Fisher in the BBC TV series Doctors.

His film credits include roles in North Sea Hijack (1979), Remembrance (1982), Haunters of the Deep (1984), Speaking of the Devil (1991), and Red Rose (2005).