This study introduces a chiral hybrid lead halide (CHLH) material system, R/S-DPEDPbBr3·H2O, which can directly produce circularly polarized second harmonic generation (CP-SHG) through linearly polarized infrared light excitation. The material exhibits a high polarization efficiency of up to 37% at room temperature. The unique zigzag inorganic frameworks within the hybrid structure reduce dielectric confinement and exciton binding energy, enhancing spin polarization. The high polarization ratio is attributed to strong spin-orbit coupling in the valence band and weak spin-orbit coupling in the conduction band, as well as the anisotropic noncentrosymmetric polar structure. Theoretical analysis using density functional theory (DFT) confirms the presence of strong spin-orbit coupling and reduced spin relaxation rates, contributing to the high CP-SHG polarization ratio. The material also demonstrates strong third harmonic generation (THG) signals and high laser damage thresholds, making it a promising candidate for various optoelectronic applications.This study introduces a chiral hybrid lead halide (CHLH) material system, R/S-DPEDPbBr3·H2O, which can directly produce circularly polarized second harmonic generation (CP-SHG) through linearly polarized infrared light excitation. The material exhibits a high polarization efficiency of up to 37% at room temperature. The unique zigzag inorganic frameworks within the hybrid structure reduce dielectric confinement and exciton binding energy, enhancing spin polarization. The high polarization ratio is attributed to strong spin-orbit coupling in the valence band and weak spin-orbit coupling in the conduction band, as well as the anisotropic noncentrosymmetric polar structure. Theoretical analysis using density functional theory (DFT) confirms the presence of strong spin-orbit coupling and reduced spin relaxation rates, contributing to the high CP-SHG polarization ratio. The material also demonstrates strong third harmonic generation (THG) signals and high laser damage thresholds, making it a promising candidate for various optoelectronic applications.