This article reviews the development and applications of superparamagnetic iron oxide nanoparticles (SPIONs) as drug delivery vehicles. SPIONs, with diameters ranging from 10 to 100 nm, are coated with biocompatible polymers to enhance their blood distribution and improve therapeutic efficiency. They are guided to target sites using an external magnetic field, making them useful for targeted drug delivery, diagnostic imaging, and gene therapy. Key aspects discussed include the preparation methods, physicochemical characteristics, drug loading techniques, targeting strategies, and elimination pathways of SPIONs. Despite their potential, concerns about toxicity, iron homeostasis, oxidative stress, and cellular responses need to be addressed before widespread clinical use. The review highlights the advantages and limitations of SPIONs, emphasizing their role in cancer therapy, gene delivery, and hyperthermia treatment.This article reviews the development and applications of superparamagnetic iron oxide nanoparticles (SPIONs) as drug delivery vehicles. SPIONs, with diameters ranging from 10 to 100 nm, are coated with biocompatible polymers to enhance their blood distribution and improve therapeutic efficiency. They are guided to target sites using an external magnetic field, making them useful for targeted drug delivery, diagnostic imaging, and gene therapy. Key aspects discussed include the preparation methods, physicochemical characteristics, drug loading techniques, targeting strategies, and elimination pathways of SPIONs. Despite their potential, concerns about toxicity, iron homeostasis, oxidative stress, and cellular responses need to be addressed before widespread clinical use. The review highlights the advantages and limitations of SPIONs, emphasizing their role in cancer therapy, gene delivery, and hyperthermia treatment.