Abstract The development of 1D stimuli‐responsive ultrathin organic nanomaterials (UTONMs)‐based hybrid nanocomposites with tailored functions is necessitated to construct hybrid catalysts with adjustable catalytic performance. Herein, the self‐assembly of ternary amphiphilic alternating azopeptoids into micron‐scaled ultrathin peptoid nanobelts (PNBs) is reported with a thickness of ≈2.2 nm. The pendants hydrophobic conjugate stacking mechanism is accountable for the formation of 1D long‐ranged‐ordered nanostructure, whose thickness is highly dependent on the length of the suspended side‐chains. The photo‐triggered reversible transition from PNBs to nanospheres (≈92 nm) is rendered by the photo‐isomerization of azobenzene moiety upon alternating irradiation with UV and visible lights. Moreover, the carboxyl‐modified aggregates are employed as supports to load Pd nanoparticles, successfully preparing hybrid nanocomposites. As a proof‐of‐concept experiment, the catalytic activity of both control and these hybrid nanocomposites are evaluated toward chemo‐enzymatic cascade catalysis for 3,3′,5,5′‐tetramethylbenzidine oxidation with in situ UV–vis spectroscopic monitor. Compared to nanospheres‐based systems, PNBs‐based nanocomposites exhibited larger catalytic performance, attributable to the ultrathin nanostructures and subsequent ultrahigh specific surface area. The photo‐controllable recyclable catalytic activity is effectively modulated using the alternative irradiation with UV and visible lights for three cycles. The work paves an appealing avenue to prepare UTONMs‐based stimuli‐responsive hybrid nanocomposites with controllable performance.