This work demonstrates the design of an in-plane polarized electric field induced by the hydrogen bonding and p-p stacking of amide-functionalized PDI supramolecules (sAmi-PDI), which are synthesized via a simple method in an acid medium. Acid-driven self-assembly is achieved via changing the local electrostatic interactions during intermolecular sAmi-PDI contact. A process that appropriately directs and accelerates the in-plane polarized electric field could improve the photoelectric separation efficiency. Moreover, p-p stacking and hydrogen-bond networks construct bridges for the molecule-molecule transfer of photogenerated electron-hole pairs, providing powerful assistance to enhance in-plane polarization. Meanwhile, the functionalized PDI molecules contain a large number of electron donors and acceptors in an acid medium; this is beneficial for improving the degree of self-assembly and providing a driving force for the efficient migration and separation of electron-hole pairs. Benefiting from the above-mentioned in-plane polarization and bridging role of electron-hole pairs, the photocatalytic performance of sAmi-PDI was dramatically enhanced almost 2-fold during the photodegradation of typical organic pollutants. Our results suggest that the enhanced photocatalytic activity could be attributed to fast carrier separation and migration caused by the in-plane polarized electric field, originating from hydrogen-bond networks and p-p stacking structures. This finding could provide a brand-new strategy for guiding the synthesis of PDI supramolecules with in-plane polarization, and could contribute to the construction of green, economical, and sustainable supramolecular materials. This journal is