The Star Trek: The Next Generation actor will appear in the upcoming fourth season of the Syfy drama in a recurring role.
Spiner will feature for at least six episodes as the character Brother Adrian, the leader of a sect known as the Brotherhood of the Knights of the Black Diamond, reports TV Guide.
Explaining Spiner's role, producer Jack Kenny said: "Artie Nielsen [Saul Rubinek] and the gang are on a mission to pull their lives back together and Brother Adrian is a major obstacle to that.
"The Brotherhood is descended from the Knights Templar and connected to the Vatican. It is charged with the protection of many powerful artefacts, one of which Artie desperately needs to make everything right again.
"The Brotherhood will do anything to achieve its goals. They are gifted fighters who are willing to go to their deaths, if necessary."
The role will see Spiner reunited with Rubinek, the two having previously appeared opposite each other in an episode of Star Trek which saw Spiner's character Data get kidnapped by collector Kivas Fajo (Rubinek).
"It's been a blast watching these two great actors go at each other again," Kenny added. "Our fans are in for one wild ride!"
Being Human actor Sam Huntington has also joined the cast.
Warehouse 13 will return for its fourth season on July 23.