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S.R. and S.S. contributed equally to this work. This work was mainly supported by the Natural Science Foundation of China (Grant No. 11874076), National Science Associated Funding (NSAF, Grant No. U1530402), and Science Challenging Program (Grant No. TZ2016001). D.E. thanks the financial support from Spanish MINECO under Grant No. MAT2016-75586-C4-1-P and from Generalitat Valenciana under Grant Prometeo/2018/123, EFIMAT. The X-ray diffraction measurements were performed at the BL15U1 station, Shanghai Synchrotron Radiation Facility (SSRF) in China. The HP XAS measurements were performed at 20 ID-C, APS, ANL. APS is supported by DOE-BES, under contract no. DE-AC02-06CH11357. The authors gratefully acknowledge Professor T. Irifune for providing the nanodiamonds for the HP XAS measurements, and K. Yang (SSRF), A. G. Li (SSRF), and C. J. Sun (APS) for their support in the in situ HP measurements. ; Inverse photoconductivity (IPC) is a unique photoresponse behavior that exists in few photoconductors in which electrical conductivity decreases with irradiation, and has great potential applications in the development of photonic devices and nonvolatile memories with low power consumption. However, it is still challenging to design and achieve IPC in most materials of interest. In this study, pressure-driven photoconductivity is investigated in n-type WO3 nanocuboids functionalized with p-type CuO nanoparticles under visible illumination and an interesting pressure-induced IPC accompanying a structural phase transition is found. Native and structural distortion induced oxygen vacancies assist the charge carrier trapping and favor the persistent positive photoconductivity beyond 6.4 GPa. The change in photoconductivity is mainly related to a phase transition and the associated changes in the bandgap, the trapping of charge carriers, the WO6 octahedral distortion, and the electron–hole pair recombination process. A unique reversible transition from positive to inverse photoconductivity is observed during compression and decompression. The origin of the IPC is intimately connected to the depletion of the conduction channels by electron trapping and the chromic property of WO3. This synergistic rationale may afford a simple and powerful method to improve the optomechanical performance of any hybrid material. ; Natural Science Foundation of China (Grant No. 11874076); National Science Associated Funding (NSAF, Grant No. U1530402); Science Challenging Program (Grant No. TZ2016001); Spanish MINECO MAT2016-75586-C4-1-P; Generalitat Valenciana under Grant Prometeo/2018/123, EFIMAT; Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART²