The R551 is a Regional Route in Gauteng, South Africa that connects Evaton and Orange Farm with the Suikerbosrand Nature Reserve via Meyerton.

[1] Its western terminus is a junction with the R553 (Golden Highway) south of Drieziek.

It begins by heading eastwards as Saint Patrick Road, separating Evaton in the Emfuleni Local Municipality to the south from Orange Farm in the City of Johannesburg Metropolitan Municipality to the north.

It then reaches a T-junction, where it becomes Rose Road north-eastwards and enters the Midvaal Local Municipality to reach a T-junction with the R82 (Old Johannesburg Road) in De Deur.

It passes by the southern end of the village of Henley on Klip (crossing the Klip River) and proceeds to cross the R557 before reaching its eastern terminus at an intersection with the R42 near the south-western corner of the Suikerbosrand Nature Reserve (16 kilometres west-south-west of Heidelberg).