Provincial Trunk Highway 77 (PTH 77) is a provincial highway in the Canadian province of Manitoba. It runs from the Saskatchewan boundary (where it meets Highway 3) near Westgate to PTH 10 near Baden. It was designated in 1987, replacing PR 277.

PTH 77 begins in Division No. 19 at the Saskatchewan border, with the road continuing west across the Armit River towards Armit and Hudson Bay as Saskatchewan Highway 3 (Hwy 3). Immediately bypassing Westgate, the highway heads east through rural woodlands for several kilometers, running along the northern border of the Porcupine Hills and Porcupine Provincial Forest. After passing National Mills and crossing several creeks, it travels through the town of Barrows to have an intersection with Red Deer Lake Road, which provides access to the community of Red Deer Lake and the lake of the same name. PTH 77 winds its way southeast through remote woodlands, traveling through Powell and Baden as well as crossing the Rice River, before entering the Rural Municipality of Mountain and coming to an end at an intersection with PTH 10 (Northern Woods and Water Route) just north of Mafeking along the banks of the Steeprock River.

The entire length of Manitoba Highway 77 is a rural, paved, two-lane highway.

Division	Location	km	mi	Destinations	Notes
Division No. 19	Westgate	0.0	0.0	Highway 3 west – Armit, Hudson Bay	Western terminus; Saskatchewan border; road continues east as Hwy 3
		1.0	0.62	Williamson Road – Westgate
		1.5	0.93	Delowski Road – Westgate
	National Mills	6.4	4.0	Twilight Street – National Mills
	Barrows	16.0	9.9	Red Deer Lake Road – Red Deer Lake
	Baden	32.8	20.4	Main Street – Baden
Mountain	​	42	26	PTH 10 (NWWR) – The Pas, Swan River	Eastern terminus
1.000 mi = 1.609 km; 1.000 km = 0.621 mi