The Boston Harbor Islands National Recreation Area is a national recreation area situated among the islands of Boston Harbor of Boston, Massachusetts. The area is made up of a collection of islands, together with a former island and a peninsula, many of which are open for public recreation and some of which are very small and best suited for wildlife. The area is run by the Boston Harbor Islands Partnership. It includes the Boston Harbor Islands State Park, managed by the Commonwealth of Massachusetts. Twenty-one of the 34 islands in the area are also included in the Boston Harbor Islands Archeological District.

A national recreation area (NRA) is a protected area in the United States established by an Act of Congress to preserve enhanced recreational opportunities in places with significant natural and scenic resources. There are 40 NRAs, which emphasize a variety of activities for visitors, including hiking, camping, boating, fishing, swimming, biking, horseback riding, and wildlife viewing, in areas that include multiple-use management for both conservation and limited utilization of natural resources. They have diverse features and contexts, being established around reservoirs, in urban areas, and within forests. Due to their size, diversity of activities, and proximity to population centers, NRAs are among the most visited units of the National Park System, with six among the thirty most visited sites.