The impact of radiation on Si-based detectors has garnered interest due to the observed degradation in their stability in high-radiation environments. In this study, we examined the effects of 3 MeV proton irradiation on both undoped and Al-doped n-Si diodes using I-V technique. The results revealed a decline in current trends for both types of diodes post-irradiation. This decrease is attributed to defects created by proton irradiation, which acts as recombination or trapping centres. However, the Al-doped n-Si diodes experienced a lesser decline in measured current, hinting at the radiation suppression effect of Al doping in Si. Additionally, Al-doped n-Si diodes displayed minimal changes in their diode parameters after irradiation, and their conduction mechanism remained unchanged. This suggests that Al-doped n-Si diodes have superior stability compared to their undoped counterparts, implying that the presence of Al enhances the diodes' resistance to radiation. The radiation suppression effect of Al seems to stem from its ability to produce defects that boost Si's radiation-hardness, thereby mitigating the introduction of additional instability-causing defects during proton irradiation. Thus, incorporating Al is recommended for research aiming to improve the radiation resistance of Si.