To provide a fork extension sleeve capable of preventing sliding of a pallet on a fork and considerably improving the service life of a non-slip member by surely preventing damage and peeling at an end part of the non-slip member.

This fork extension sleeve 8 is attachably/detachably fitted to the fork 5 inserted into the pallet P. The sheet-like non-slip member 10 to prevent sliding of the pallet P is arranged on an upper surface of a fork extension sleeve main body 9. A plate-like protective member 11 to protect the non-slip member 10 is arranged at a pallet insertion side end part of the non-slip member 10. The protective member 11 is attachably/detachably fixed to the fork extension sleeve main body 9. In the protective member 11, a cover part 23 superimposed on the non-slip member 10 and an inclined guide part 21 arranged on the pallet insertion side from the cover part 23 are formed.