The present disclosure provides an anti-PD-L1/anti-LAG3 bispecific antibody capable to effectively block the interactions between PD-L1 and its receptor PD-1 and between LAG3 and its ligand (e.g., a MHC class II molecule and FGL1). The bispecific antibody may have high binding affinity to both of a PD-L1 protein (e.g., a human PD-L1 protein) and a LAG3 protein (e.g., a human LAG3 protein). Also provided are antibodies and fragments that have specificity to the PD-L1 or LAG3 protein alone, or antibodies and fragments having additional specificity to one or more other antigens.