Head coach Allister Coetzee, opting to rest almost his entire squad, has handed starts to Harris, fit-again Springbok hooker Tiaan Liebenberg and flyhalf Kurt Coleman, who will make his 50th appearance for Province.
A familiar face on the bench this week is that of former Western Province captain Anton van Zyl, who joins the match-day squad following injuries to first-choice locks Jean Kleyn and Ruan Botha.
Western Province have already qualified for a home semifinal, by virtue of their top of the log finish with a game in hand.
Harris, who will be leaving Western Province at the end of the season – after eight years in the Cape – has played 117 matches for Western Province and the Stormers.
Inside centre Jaco Taute was not considered for selection due to a rib injury with Michael van der Spuy and Pat Howard combining at centre this week.
Western Province: Dillyn Leyds, EW Viljoen, Pat Howard, Michael van der Spuy, Devon Williams, Kurt Coleman, Louis Schreuder, Sikhumbuzo Notshe, Rynhardt Elstadt, Rohan Kitshoff, Gerbrandt Grobler, Jurie van Vuuren, Brok Harris (capt), Tiaan Liebenberg, Oli Kebble
Bench: Neil Rautenbach, Justin Ackerman, Gavin Annandale, Anton van Zyl, Patrick O’Brien, . Godlen Masimla, Chevandre van Schoor