The Manus Plate is a 100-km microplate located northeast of New Guinea. The Manus Plate was formed in between the North Bismark Plate and the South Bismark Plate. The Manus Plate currently rotates counter-clockwise in the Melanesia area.^[1]

The Manus Plate formed during the Brunhes-Matuyama reversal, making its maximum age approximately 781,000 years old.^[2] The Manus Plate formed in-between and on top of the transform boundaries that were separating the North and South Bismark plates.^[2] The plate was formed of young mid-ocean ridge basalt, along with pieces of older oceanic floor that had broken off of the South Bismarck plate.^[2]

The north and northeast boundaries of the Manus Plate, with the North Bismark and Pacific plates are both convergent boundaries.^[3] The plates southeast borders of the South Bismark plate is a divergent boundary.^[3] The southwest boundary bordering the South Bismark plate is a transform boundary. The Manus plate currently has a rate of rotation of 51°/ Ma at the spot, -3.04°N, 150.46°E, in the counter-clockwise direction, due to the plates left lateral motion.^[4] This is likely the fastest plate rotation, on Earth at this time.^[4]