Transgenic rice with cleavable chimeric polyprotein was generated. The polyprotein precursor consists of a leader peptide and two different antimicrobial proteins (AMPs); Dm-AMP1 and Rs-AFP2. Plants transformed with polyprotein construct showed significantly improved disease resistance against Magnaporthe oryzae and Rhizoctonia solani. The chimeric polyprotein was cleaved and present in equimolar concentration in transgenic rice, and the individual AMPs were secreted into the extracellular space. The results of in vitro, in planta, and microscopic analyses suggest that chimeric polyprotein expression has the potential to provide broad-spectrum disease resistance in rice.