The heavyweight fighter, who will make his comeback in June, described the WBA, IBF and WBO belt holder as a "big old dosser" and vowed to knock him out if they ever meet in the ring.
"[Joshua] is a big old dosser – he is a belt carrier for me. By the time I get ready to fight, it is going to be an easy fight, no contest," Boxing News quotes Fury as saying.
"He is looking for one punch all night. We all saw the [Joseph] Parker affair - anybody who can move a bit and throw a few feints, he struggles, he can't land on."
Fury accepted a backdated two-year ban from UK Anti-Doping after testing positive for a prohibited substance almost three years ago.
The 29-year-old, who has been preparing for his return to the ring since January when the suspension on his boxing licence was lifted, will fight an unnamed opponent at the Manchester Arena on June 9.