Provided is an isolated monoclonal antibody or an antigen-binding fragment thereof combating the human PD-1, comprising heavy chains CDR1, CDR2 and CDR3 listed in Table 2 and light chains CDR1, CDR2 and CDR3 listed in Table 2.本發明提供了針對人PD-1的分離的單株抗體或其抗原結合片段,包含表2中所列的重鏈CDR1、CDR2和CDR3以及表2中所列的輕鏈CDR1、CDR2和CDR3。