Tinicum Township, also known as Tinicum Island or The Island, is a township in Delaware County, Pennsylvania, United States. The population was 4,091 at the 2010 census, down from 4,353 at the 2000 census. Included within the township's boundaries are the communities of Essington and Lester.

The John Heinz National Wildlife Refuge at Tinicum is a 1000-acre (4.05 km2) National Wildlife Refuge in Philadelphia and Tinicum Township, Pennsylvania. Adjacent to Philadelphia International Airport, the refuge is designed to the largest remaining freshwater tidal marsh in Pennsylvania. Established in 1972 as the Tinicum National Environmental Center, it was renamed in 1991 after the late H. John Heinz III, who helped preserve Tinicum Marsh.