The present application provides a recombinant fusion protein containing an anti-CD24 antibody or an antibody fragment thereof, with at least one paratope of the anti-CD24 antibody or antibody fragment thereof linked via a linker to an extracellular Ig-like domain of a signal-regulatory protein (SIRP) at N-terminus of a heavy chain or a light chain constituting that paratope, wherein the recombinant fusion protein can bind to CD47, CD24 and FcR simultaneously. The present application also provides a nucleic acid molecule encoding the recombinant fusion protein, an expression vector containing the nucleic acid molecule, a method for producing the recombinant fusion protein and a method for treating a disease associated with over expression of CD47 and/or CD24 using the recombinant fusion protein.