This study introduces a novel proton-promoted in-situ ligand exchange strategy for CsPbI3 quantum dots (QDs) to enhance their stability and photophysical properties. The method involves using hydroiodic acid (HI) to dissolve short-chain 5-aminopentanoic acid (5AVA) ligands, which then exchange with long-chain oleic acid (OA) and oleylamine (OAm) ligands on the QDs surface. This process maintains the quantum confinement effect of the QDs while improving their stability and optical properties. The resulting CsPbI3 QDs exhibit a maximum external quantum efficiency (EQE) of 24.45% and a half-operational lifetime of 10.79 hours, representing a 70-fold improvement over control devices. The study demonstrates that this ligand exchange strategy effectively passivates surface defects, reduces non-radiative recombination, and enhances charge transfer, leading to significantly improved performance in red QD-based light-emitting diodes (QLEDs).This study introduces a novel proton-promoted in-situ ligand exchange strategy for CsPbI3 quantum dots (QDs) to enhance their stability and photophysical properties. The method involves using hydroiodic acid (HI) to dissolve short-chain 5-aminopentanoic acid (5AVA) ligands, which then exchange with long-chain oleic acid (OA) and oleylamine (OAm) ligands on the QDs surface. This process maintains the quantum confinement effect of the QDs while improving their stability and optical properties. The resulting CsPbI3 QDs exhibit a maximum external quantum efficiency (EQE) of 24.45% and a half-operational lifetime of 10.79 hours, representing a 70-fold improvement over control devices. The study demonstrates that this ligand exchange strategy effectively passivates surface defects, reduces non-radiative recombination, and enhances charge transfer, leading to significantly improved performance in red QD-based light-emitting diodes (QLEDs).