Abstract: Root morphology and physiological characteristics are closely related to nutrient and water use efficiency of crops. Root mutants are powerful tools for studying root structure and function. In recent decades, a number of mutants specifically affecting maize root development have been identified. Among the mutants, rtcs is defects in the development of crown root, lrt1, slr1, slr2, and rum1 are defective in lateral root development, and rth1, rth2, and rth3 are defective in the development of root hairs. Some underlined genes of the mutants have been cloned. These materials and gene information will facilitate the understanding the role of maize root in efficient use of nutrient and water resources.