Recombinant Anti-CD89 x Anti-S. pneumoniae Bispecific Antibody (Miniantibody) is a fusion protein of two scFv fragments combined with distinct specificity. One scFv of an anti-CD89 antibody variable domain is linked to another scFv of an anti-S. pneumoniae antibody variable domain by a flexible hinge region. This BsAb format has the decreased size and better penetration than conventional IgGs in the clinical diagnostics and potentially therapy. This BsAb can retarget NK cells to genus plasmodium. It is designed for the research of S. pneumoniae infection therapy.