Grevillea parallelinervis is a shrub of the genus Grevillea native to South Australia. The spreading shrub typically grows to a height of 0.5 to 2 metres (2 to 7 ft) and has terete branchlets. It has simple linear leaves with a blade that is 25 to 90 millimetres (1.0 to 3.5 in) long and 0.7 to 1.5 mm (0.03 to 0.06 in) wide. It blooms from August to October and produces an axillary raceme regular inflorescence with red or pink flowers and red-pink styles with green to yellow tips. Later it forms smooth ellipsoidal glabrous fruit that is 13.5 to 17 mm (0.5 to 0.7 in) long.