Recombinant Anti-CCR3 x Anti-CD300 Bispecific Antibody (Fab-scFv-Fc) requires expression of three polypeptide chains, encoding two heavy chains (Fc-containing chains) and one light chain, respectively. The Fab of anti-CCR3 antibody variable domain is fused to the Fc-knob domain with a hinge region and the same as the scFv of anti-CD300 to the Fc-hole domain, or vice versa. The Fab-Fc and scFv-Fc fragments can be paired via the interaction of the Fc regions. This BsAb canreduce eosinophil signaling, inhibit bronchoalveolar lavage fluid inflammation, eosinophil, mast cell mediator release and reverse lung inflammation. It is designed for the research of Asthma therapy.