National Park Sjeverni Velebit (lit. Northern Velebit; Croatian: Nacionalni park Sjeverni Velebit) is a national park in Croatia that covers 109 km² of the northern section of the Velebit mountain, the largest mountain in Croatia. Because of the abundant variety of this part of the Velebit range and its authenticity, the area was upgraded from its classification as a nature reserve to a national park in 1999, and started work in September the same year.