Mira River Provincial Park is a provincial park situated on the Mira River in Cape Breton County, Nova Scotia, 22 kilometres (14 mi) from Sydney and 17 kilometres (11 mi) from the Fortress of Louisbourg National Historic Site of Canada. Opened in 1967, the 87.49 hectares (216.2 acres) property offers camping sites and a range of opportunities for outdoor recreation, including picnicking, swimming, canoeing, kayaking, biking, front-country hiking, boating, fishing, cross-country skiing, snowshoeing, and geocaching.

Lands were initially acquired for the park in 1962, with major acquisitions occurring in 1968 and 1973. The property was designated under the Provincial Parks Act by Order in Council (OIC 84-679) on 12 June 1984. In an area of almost exclusively private properties, the park provides one of the few public access points to the Mira River.

The Mira River Valley is a dominant topographical feature of southeastern Cape Breton Island, extending from Framboise Cove northwards to about Marion Bridge and then sweeping eastwards to exit at Mira Bay. The river lies between 320 million year old Carboniferous formations to the north and 500 million year old Cambrian and Precambrian formations to the south. The highly eroded bedrock is covered by a thick layer of glacial till, sands and gravels deposited during the retreat of the last ice age some 15,000 years ago.

Lying in a long narrow valley, possibly along an old fault line, the lower reaches of the river have been dammed by glacial gravels to form a long lake. Along the lower two-thirds of the river, these glacial deposits also formed numerous peninsulas such as the one Mira River Provincial Park occupies. About three kilometres from the mouth of the Mira, the river narrows and cuts a valley through bedrock to reach the Atlantic Ocean. Here the valley is less than 50 metres (160 ft) wide, with banks 20 metres (65 feet) high.

The carboniferous bedrock to the north of the Mira includes numerous coal seams - evidence of the area's environment 300 million years ago. At that time shallow lakes, bays, swamps and coastal flood plains covered much of the region. Abundant fossils can be found in this coal. These coal seams supported the region's long history of coal mining. South of the Mira, fossils are also imbedded in the Cambrian sandstones and shales.

The Mira River has a drainage area of approximately 648 square kilometres (250 sq mi), with the Gaspereau, Salmon and Trout rivers, along with Black Brook, as its main tributaries. Along the southern part of its course, glacial deposits have interrupted the flow to form a chain of small lakes which are all less than 15 metres above sea level. Tidal waters move back and forth in the eastern portion of the river, although the influx of salt water any distance beyond the river mouth is limited.

The waters of the Mira River support a variety of fish species including sea trout, shad, perch, American eels, striped bass, mackerel, herring, brook trout, speckled trout, minnows and smelts. Consequently, the river is popular for fishing.

The forest cover of Mira River Provincial Park consists generally of tolerant hardwoods, predominantly sugar maple, on the westernmost portion near Joes Point, with a larger portion of mixed woods through the central portion and softwood stands along the western shoreline, around the maintenance yard and immediately south of the northernmost walk-in campsites. Large areas of non-forested areas are associated with the campground. A six hectare wetland is located along the northernmost shoreline. Portions of the park remain relatively undisturbed and in a region with a long history of human development provide an opportunity to explore and appreciate the area's natural heritage.