Tybee NWR was established on May 9, 1938 as a breeding area for migratory birds and other wildlife. The majority of the 100-acre refuge is covered with sand deposits from the U.S. Army Corps of Engineers' dredging activities in the Savannah River. The more stable portions of the island are densely covered with such woody species as eastern red cedar, wax myrtle, and groundsel. Saltwater marsh borders parts of the island. At low tide the shoreline provides a resting and feeding place for many species of migratory birds.

The refuge is located in the mouth of the Savannah River, adjacent to the Georgia state line and directly opposite Fort Pulaski National Monument which is 12 miles east of Savannah on U.S. Highway 80. Tybee NWR is closed to public use. Tybee NWR is one of seven refuges administered by the Savannah Coastal Refuges Complex. This chain of national wildlife refuges extends from Pinckney Island NWR near Hilton Head Island, South Carolina, to Wolf Island NWR near Darien, Georgia. Between these lie Savannah (the largest unit in the complex), Wassaw, Tybee, Harris Neck, and Blackbeard Island refuges. Together they span a 100-mile coastline and total 56,949 acres. The Savannah Coastal Refuges are administered from headquarters located in Savannah, Georgia.

This 100-acre migratory bird refuge began as a one-acre oyster shoal. The U.S. Army Corps of Engineers (COE), while engaged in river and harbor improvements, used the shoal as a spoil site. Accumulated spoil created Oysterbed Island (the nucleus of the present refuge). Title to Oysterbed Island was conveyed to the United States by the state of Georgia on December 30, 1820. Since that time, the COE has continued to use the area as a spoil site. Accumulated spoil eventually joined Oysterbed Island and Jones Island to form the north bank of the Savannah River.

Tybee NWR was established by Executive Order No. 7882 on May 9, 1938 "in order to effectuate further the purposes of the Migratory Bird Conservation Act". In the enabling legislation, the United States Coast Guard (USCG) retained control over a one-acre site known as the Oysterbed Lighthouse Reservation and the COE retained the authority to deposit soil on the refuge. The legislation does stipulate "that any accretions thereto resulting directly or indirectly from river and harbor improvement work shall when formed become part of the refuge". The USCG transferred the Day Beacon Tower and surrounding area (formerly the Oysterbed Lighthouse Reservation) to the U.S. Fish and Wildlife Service on February 17, 1960.