The von Willebrand factor (VWF) propeptide (domains D1D2), is essential for the assembly of VWF multimers and its tubular storage in Weibel-Palade bodies. However, detailed molecular mechanism underlying this propeptide dependence is unclear. Here we prepared Weibel-Palade body-like tubules using the N-terminal fragment of VWF and solved the cryo-EM structures of the tubule at atomic resolution. Detailed structural and biochemical analysis indicate that the propeptide forms a homodimer at acidic pH through the D2:D2 binding interface and then recruits two D'D3 domains forming an intertwined D1D2D'D3 homodimer in essence. Stacking of these homodimers by the intermolecular D1:D2 interfaces brings two D3 domains face-to-face and facilitates their disulfide linkages and multimerization of VWF. Sequential stacking of these homodimers leads to a right-hand-helical tubule for VWF storage. The clinically identified VWF mutations in the propeptide disrupted different steps of the assembling process leading to diminished VWF multimers in von Willebrand diseases (VWD). Overall, these results indicate that the propeptide serves as a pH sensing template for VWF multimerization and tubular storage. This sheds light on delivering normal propeptide as template to rectify the defects in multimerization of VWD mutants.