Diabetes mellitus (DM) is a chronic disease characterized by hyperglycemia, dyslipidemia, nephropathy, and oxidative stress, highlighting the need for innovative therapeutic strategies. This study investigated the potential of green-synthesized silver nanoparticles (Ag NPs), prepared using Moringa oleifera (M. oleifera) leaf extract, to mitigate diabetes-related complications in a streptozotocin (STZ)-induced diabetic rat model. Silver nanoparticles were synthesized via a green method and characterized using transmission electron microscopy (TEM). Fifty adult albino rats were divided into five groups: Group I (control), Group II (diabetic), Group III (diabetic treated with Ag NPs), Group IV (diabetic treated with M. oleifera), and Group V (diabetic receiving combination therapy). Biochemical parameters related to renal function, lipid profile, and antioxidant biomarkers were measured, along with a histological examination of kidney tissue. Combination treatment exhibited superior therapeutic efficacy, significantly reducing fasting blood glucose, HbA1c, total cholesterol, triglycerides (TG), and low-density lipoprotein cholesterol (LDL-c) while increasing high-density lipoprotein cholesterol (HDL-c). Additionally, antioxidant biomarkers improved, with elevated levels of glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT), alongside a reduction in malondialdehyde (MDA). These effects were accompanied by significant histological improvements in kidney architecture, indicating nephroprotective properties. Transmission electron microscopy confirmed the formation of uniform, spherical Ag NPs, while combination treatment demonstrated synergistic effects, suggesting that M. oleifera enhances nanoparticle efficacy through its antioxidant properties. This study underscores the therapeutic potential of green-synthesized Ag NPs and M. oleifera leaf extract as a promising approach for managing DM and its complications.