Applications of nanomaterials in many areas of human endeavors including industry, agriculture, business, medicine and public health are increasing day by day. The enormous capabilities of nanomaterials in health sector have been especially potentiated and ensured with their advanced uses in tissue engineering, biomedical processes, and relevant areas. Applications for some of the nanoparticles included biomedical implants, tailored pharmaceutical goods, new diagnostic tools, imaging, and associated techniques. Despite their worthy benefits, the exposure of nanomaterials tohealth and environmental becomesan inevitable consideration as the toxicity of nanomaterials are gaining much attention in recent time. The unintentional harm of nanomaterials to our health is making further development difficult. Therefore, toxicity of nanomaterials and their health impacts are indispensably needed to be attained. This book chapter summarizes the advanced use of nanomaterials, recent research efforts on the toxicological impacts on health, and a critical evaluation of challenges and future needs for the safe applications of nanomaterials.