The present invention provides PD-1 monoclonal antibodies, particularly human monoclonal antibodies of PD-1, which specifically bind to PD-1 with high affinity and comprise a heavy chain and a light chain. The present invention further provides nucleic acid sequence encoding the antibodies of the invention, cloning or expression vectors, host cells and methods for expressing or isolating the antibodies. Immunoconjugates, therapeutic compositions comprising the antibodies of the invention are also provided. The invention also provides methods for treating various cancers with anti-PD-1 antibodies.
