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Several HD-ZIP IV transcription factors have been reported to play important roles in plant growth and development. However, the functions of most members remain unknown. In this study, an HD-ZIP IV transcription factor, AmHDG1, was identified from desert shrub Ammopiptanthus mongolicus (Leguminosae) by RACE PCR. AmHDG1 consists of 2,508 bp, has an open reading frame of 2,292 bp, and encodes a predicted polypeptide of 763 amino acids. Phylogenic analysis with the HD-ZIP IV transcription factor family of Arabidopsis showed that it is clustered with the subfamily of AtHDG1 and AtANL2. AmHDG1 is localized in the nucleus and is able to activate transcription in yeast. In A. mongolicus, AmHDG1 is preferentially expressed in young leaves. Constitutive overexpression of AmHDG1 results in upcurved leaves and non-dehiscent anthers in Arabidopsis thaliana. In the flowers of AmHDG1 overexpressors, the expression levels of two positive regulators of anther dehiscence, AtNST1 and AtNST2, are down-regulated. On the other hand, the transcript level of another positive regulator, AtMYB26 is not influenced. Taken together, our data demonstrate that AmHDG1 plays a negative role in the regulation of anther dehiscence.