Antimicrobial peptides, small molecular weight proteins with broad spectrum antimicrobial activity, play important roles in plant defense responses. The open-reading-frame sequence of AcAMP-sn was synthesized and used to construct the gene transformation vector pAHC25::AcAMP-sn, in which AcAMP-sn gene was driven by maize ubiquitin promoter and should be highly expressed in monocot plants. The vector pAHC25::AcAMP-sn DNA was introduced into Yangmai 18 via particle bombardment. AcAMP-sn transgenic wheat plants were subjected to PCR, semi-RT-PCR, Q-RT-PCR analyses, and disease response assessments. PCR analyses revealed that the introduced gene AcAMP-sn could be stably inherited in five transgenic wheat lines from T 0 to T 4 generations. Semi-RT-PCR and Q-RT-PCR analyses showed that the AcAMP-sn gene was highly expressed in transgenic wheat lines compared with untransformed Yangmai 18. Based on disease response assessments for T 4 generations, the significantly enhanced-resistance to take-all accompanied with decreased fungal abundance, in the five independent AcAMP-sn transgenic lines. Over-expression of AcAMP-sn gene in transgenic wheat plants confers increased resistance to wheat take-all.