To elucidate the molecular mechanism of leaf erectness in wheat，this study analyzed the differentially expressed genes （DEGs） using the transcriptome sequencing in a wheat erect leaf mutant MtHS29，which was identified using fast neutron irradiation in the wild type cultivar Heng S29 . The leaves from MtHS29 were observed with degrees of deficiency with leaf pillow，ligule and auricle，in which the flag leaf and the second leaf from top lacked all of these structures and their leaf angles approached to zero. A total of 1567 DEGs were found in the leaf pillow of the second，third and fourth leaves from top between MtHS29 and WT. These genes were enriched in the pathways of plant hormone signal transduction，starch and sucrose biosynthesis，phenylpropanoids biosynthesis，endoplasmic reticulum protein processing，and amino acid and nucleotide glucose metabolism，etc. A proportion of DEGs in MtHS29 were annotated closely associating to regulating the cell division and cell expansion in the proximal and distal axial surfaces of the leaf pillow，and to deficiency of leaf pillow，ligule and auricle in mutant. Several genes involved in the synthesis of cell wall components，synthesis and signal transduction of Auxin and Brassinosteroids，and regulation of plant organ morphogenesis were found. Collectively，this study provided new germplasm in wheat breeding for plant architecture，and insights for future deciphering the molecular mechanism of the erect leaf architecture in wheat.