Dendrite development is critical in the formation of functional neural networks. Recent studies have provided insights into the involvement of secretory transport in dendritogenesis, raising the question of how the secretory pathway may be under regulation to direct dendritic elaboration. Here, we identify a functional link between transcriptional regulatory programs and the COPII secretory machinery in driving dendrite morphogenesis in Drosophila dendritic arborization (da) sensory neurons. MARCM analyses and gain-of-function studies reveal cell-autonomous requirements for the COPII coat protein Sec31 in mediating da neuron dendritic homeostasis. We demonstrate that the homeodomain protein Cut transcriptionally regulates Sec31 in addition to other components of COPII secretory transport to promote dendrite elaboration, accompanied by increased satellite secretory endoplasmic reticulum (ER) and Golgi outposts primarily localized at dendritic branch points. We further establish a novel functional role for the transcription factor CrebA in regulating dendrite development and show that Cut initiates a gene expression cascade via CrebA that coordinately affects the COPII machinery to mediate dendritic morphology.