The present invention describes a bispecfic antibody composed of the variable domains (VH and VL) of two antibodies, hERG1 mAb (which binds the extracellular domain S5-P of hERG1) and of β1 integrin mAb TS2/16 or BV7, which bind the extracellular domain of β1 integrin. The present invention relates also to a novel anti-hERG1 molecule bearing a Cys in position 95 of the VH domain. The invention describes also their application for diagnostic and therapeutic purposes in oncology and other fields of medical sciences.