The 22 year-old has made 17 appearances with the Stormers and represented Western Province on 22 occasions.
From 2012 the South African native steadily progressed through the Western Province ranks establishing himself as a key player, before going on to secure regular game-time with Super Rugby side, the Stormers, from 2014.
In making the move to the province Kleyn joins his former Defence Coach Jacques Nienaber who he would have worked closely with during his time at the Cape Town franchise. The 6′ 8″ second row will join the province in August subject to being granted a valid work permit.
Commenting on the news Director of Rugby Rassie Erasmus said,