Abstract: The present invention relates to novel antibodies or antigen-binding fragments thereof that specifically bind to CD73 and compositions comprising the antibodies or antigen-binding fragments thereof. The present invention also relates to a nucleic acid encoding the antibody or antigen-binding fragment thereof of the present invention, a vector comprising the polynucleotide, a host cell comprising the nucleic acid or the vector, an immunoconjugate and pharmaceutical composition comprising the antibody or antigen-binding fragment thereof. Furthermore, the present invention relates to the uses of these antibodies or antigen-binding fragments thereof in the immunotherapy, prevention and/or diagnosis of diseases.