A chip-on-film (COF) package structure includes a first COF and a second COF. The first COF includes a first flexible substrate having a first external terminal and a first internal terminal opposite to each other, first outer leads disposed at the first external terminal, first inner leads disposed at the first internal terminal, and a first chip disposed between the first external terminal and the first internal terminal. The second COF includes a second flexible substrate having a second external terminal and a second internal terminal opposite to each other, second outer leads disposed at the second external terminal, second inner leads disposed at the second internal terminal, and a second chip disposed between the second external terminal and the second internal terminal. The first COF is partially overlapped with the second COF. A display device having the COF package structure is also provided.