Icariin (ICA), an active ingredient found in Epimedium, possesses antioxidant and anti-inflammatory properties and has garnered widespread attention in recent years. This study investigated the protective effects of ICA against cadmium (Cd)-induced kidney injury in rats. Healthy male specific pathogen-free Sprague–Dawley rats were randomly divided into a control group, Cd group, a low-dose ICA group, a middle-dose ICA group, and a high-dose ICA group using a random number table. Tissue and blood samples were analyzed for renal function markers, histopathology, and gene expression. We found that ICA intervention ameliorates Cd-induced nephrotoxicity by enhancing glomerular filtration, mitigating renal tubular epithelial cell damage, reducing cellular degeneration and edema, and decreasing oxidative stress. ICA demonstrated anti-apoptotic activity through the regulation of pro- and anti-apoptotic gene transcription and by inhibiting apoptosis, thus protecting the kidneys. ICA also exhibited anti-inflammatory effects by reducing the transcription of Cd-induced pro-inflammatory genes, inhibiting nucleotide oligomerization domain-like receptor pyrin domain-containing 3 (NLRP3) inflammasome formation, and preventing pyroptosis. ICA potentially regulated the Toll-like receptor 4/P2rx7/nuclear factor kappa B signaling pathway, which modulated the activation of the NLRP3 inflammasome and contributed to its anti-inflammatory action. ICA reduced Cd-induced renal injury in rats, likely through a mechanism involving antioxidant, anti-apoptotic, and anti-inflammatory effects.