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The basement membrane (BM) is an essential structural element of tissues, and its diversification participates in organ morphogenesis. However, the traffic routes associated with BM formation and the mechanistic modulations explaining its diversification are still poorly understood. Drosophila melanogaster follicular epithelium relies on a BM composed of oriented BM fibrils and a more homogenous matrix. Here, we determined the specific molecular identity and cell exit sites of BM protein secretory routes. First, we found that Rab10 and Rab8 define two parallel routes for BM protein secretion. When both routes were abolished, BM production was fully blocked; however, genetic interactions revealed that these two routes competed. Rab10 promoted lateral and planar-polarized secretion, whereas Rab8 promoted basal secretion, leading to the formation of BM fibrils and homogenous BM, respectively. We also found that the dystrophin-associated protein complex (DAPC) and Rab10 were both present in a planar-polarized tubular compartment containing BM proteins. DAPC was essential for fibril formation and sufficient to reorient secretion towards the Rab10 route. Moreover, we identified a dual function for the exocyst complex in this context. First, the Exo70 subunit directly interacted with dystrophin to limit its planar polarization. Second, the exocyst complex was also required for the Rab8 route. Altogether, these results highlight important mechanistic aspects of BM protein secretion and illustrate how BM diversity can emerge from the spatial control of distinct traffic routes. Author summary: Diversification of the basement membrane (BM) is crucial for tissue structure and organ development, yet the mechanisms governing its formation and diversification remain unclear. We focused on the Drosophila melanogaster follicular epithelium, characterizing BM protein secretion pathways. We identified Rab10 and Rab8 as key regulators, orchestrating parallel secretion routes. Rab10 promotes lateral and planar-polarized secretion, while Rab8 facilitates basal secretion. As a result of this highly polarized system, Rab10 route induces the formation of BM fibrils while Rab8 route generate homogenous BM. Additionally, dystrophin-associated protein complex (DAPC) is involved in fibril formation and secretion route orientation towards Rab10. Furthermore, we discovered the involvement of the exocyst complex, notably its Exo70 subunit that it interacts with dystrophin, impacting its planar polarization, and that is crucial for the Rab8 route. These findings deepen our understanding of BM protein secretion mechanisms, emphasizing the role of distinct traffic routes in BM diversity emergence. Moreover, it reveals new functions and molecular interactions for the DAPC that could be relevant for the many congenital diseases involving this complex. [ABSTRACT FROM AUTHOR]