Van Rooyen is a free agent after leaving Pirates last month and has been brought in as cover following a long-term injury to first-choice right-back Khuliso Mudau.
“This is a club built on ambition and excellence. I am here to work, grow and give everything,” Van Rooyen said.
The 29-year-old was formerly captain of Stellenbosch FC and made 134 top-flight appearances for the Winelands club, scoring three goals and providing eight assists.
He moved to Pirates ahead of the 2024/25 season and made a further 51 appearances, scoring once and providing one assist.