Consisting of foreshore only, Rock Bay juts out into the ocean at the junction of Discovery Passage and Johnstone Strait on the east coast of Vancouver Island, northwest of Campbell River.

Outdoor enthusiasts seeking marine recreation head to Rock Bay for scuba diving, canoeing, kayaking, and boating. Camping is available nearby. An entire day can easily be spent exploring this attractive shoreline and sheltered anchorage. The park protects archaeological sites, marine ecosystems and a small area of young forests on shore.

Facilities in the park include a boat launch ramp with a dock, parking, sani cans, picnic areas, and walking trails. Water is available in the park, but as the water is not tested regularly, signs indicate that the water is not potable. Visitors may prefer to bring their own drinking water.

There are no camping facilities at Rock Bay park, but a private campsite is located near the boat launch. There are also other campgrounds in the area, all maintained by the Campbell River ATV Club, including the pretty bay and camp area at Bear Bay, and campgrounds at Elk Bay, Stella Lake and Pye Lake to the south of Rock Bay.

Otter Cove on the southeastern end of the park, in the Discovery Passage, provides a sheltered anchorage for small vessels waiting to navigate the nearby tidal passes.

Rock Bay Marine Provincial Park is a rocky headland and two adjacent bays on the east coast of Vancouver Island, British Columbia, approximately 40 km northwest of Campbell River at the junction of Discovery Passage and Johnstone Strait. The park is accessible by land or water. A logging road connects the park to Highway 19.