This study aimed to investigate the potential modulatory effect of 5-Fluorouracil (5-FU) combined with L-carnitine nanoparticles (LCN) against 5-FU-induced nephrotoxicity in mice bearing, Ehrlich ascites carcinoma (EAC). Five sets of female albino mice were created. Group 1: CON, group 2: EAC induced by a single injection of 2.5 x 10⁶ EAC/ml, group 3: EAC+5-FU received 25mg/kg of 5-FU i.p, group 4: EAC+LCN received orally 50 mg/kg, and group 5: EAC+5-FU+ LCN received the same dose and route as the preceding groups. The 5-FU+ LCN group saw a considerable reduction in mean tumor weight (MTW), an elevation in life span (ILS), and an improvement in mean survival time (MST). Furthermore, 5-FU+ LCN enhanced serum creatinine, urea, and albumin levels while decreasing MDA levels, which are related to increased levels of GSH, GPX, and SOD, as well as decreased levels of TNF-α and MCP-1 in kidney tissue. Moreover, 5-FU+ LCN reduced caspase-3 and P53 levels while increasing Bcl2 levels when compared to 5-FU alone. Microscopic examination showed lesions in the kidney tissue sections of mice exposed to 5-FU. The treatment of EAC mice with 5-FU+ LCN showed an enhancement in histological structure and an antitumor effect that was more protective than induced by 5-FU alone.