Core-shell SiO2@p-CuO semiconductor composite structure-based junction diodes were fabricated by using a metal oxide semiconducting material. The core-shell SiO2@p-CuO composite structure was successfully fabricated by co-precipitation route. X-ray diffraction (XRD) and Raman spectroscopy is used to inspect the structure & vibrational modes. Field Emission SEM (FE-SEM) was used to analyse the morphology. XRD confirms the existence of monoclinic structure in the pure CuO and SiO2@p-CuO and Raman studies further establish the formation of a single-phase structure in annealed samples. Crossed nanoflakes-like surface morphology of CuO and formation of core-shell SiO2@p-CuO structure was verified with FE-SEM micrographs. Fabricated SiO2@p-CuO/n-Si junction diode shows better photo-response along with a better ideality factor of 3.96 under a light condition than the p-CuO/n-Si. The photosensitivity, responsivity, external quantum efficiency, and detectivity of the developed SiO2@p-CuO/n-Si diodes is estimated ~ 580,471.4%, ~ 259.7 mA/W, ~ 100.7%, 1.715 × 1012 Jones, respectively which are several times larger than the bare p-CuO/n-Si, which are estimated ~ 5320.3%, ~ 230.6 mA/W, ~ 89.4% and 1.561 × 1011 Jones, respectively. The enhanced photodetection properties of SiO2@p-CuO/n-Si diode proposes it as a mesmerizing aspirant for photodetector application.