Recombinant Anti-CD89 x Anti-S. pneumoniae 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-CD89 antibody variable domain is fused to the Fc-knob domain with a hinge region and the same as the scFv of anti-S. pneumoniae 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 can retarget NK cells to genus plasmodium. It is designed for the research of S. pneumoniae infection therapy.