The Peace River is a river in Canada which originates in the Rocky Mountains of northern British Columbia and flows through northern Alberta. This river is approximately 1,923 km long. It drains an area of approximately 302,500 km².

A large man-made lake, Williston Lake , has been formed on the upper river by the construction of the W.A.C. Bennett Dam for hydroelectric power generation. After the dam, the river then flows east into Alberta and then continues north and east to meet the Athabasca River at the Peace-Athabasca Delta in Wood Buffalo National Park. Water from the delta flows into the Slave River and reaches the Arctic Ocean via the Mackenzie River.

The regions along the river are the traditional home of the Dunne-za or Beaver people. The fur trader Peter Pond is believed to have visited the river in 1785. A fur trading post was established by Charles Boyer of the North West Company in 1788 at the river's junction with the Boyer River . In 1793 and 1793, the explorer Alexander Mackenzie travelled up the river to the Continental Divide. Mackenzie referred to the river as "Unjegah", from a native word meaning "large river". In 1794, a fur trading post was built on the Peace River at Rocky Mountain House, near the current site of Fort St. John, which was the first non-native settlement on the British Columbia mainland.

The rich soils of the Peace River valley in Alberta have been producing wheat crops since the late 19th century. The Peace River region is also an important centre of oil and natural gas production. There are also lumber and pulp and paper plants along the river in British Columbia.

Communities on the river include:

• Peace River, Alberta
• Fort Vermilion, Alberta

Tributaries include the:

• Halfway River
• Pine River
• Smoky River
• Cadotte River
• Wabasca River

The river was named after Peace Point near Lake Athabasca, where a dispute was settled between the Beaver and Cree people.