In this study, 134 maize inbred lines were used as experimental materials to conduct phenotypic identification of 9 root traits at seedling stage of maize, and 44935 SNP markers distributed in maize genome were used to conduct Genome-wide association study (GWAS) based on FarmCPU model. The results showed that the phenotypic variation range of 9 root traits ranged from 10.86% to 55.96%, and the correlation between most phenotypes reached a highly significant level (P<0.001). The correlation coefficient between lateral root length and total root length was the highest, reaching 0.996, followed by the number of lateral roots and total roots reaching 0.993. A total of 32 significantly associated SNP loci were identified (P=1.01e-11-9.74e-5), with phenotypic contribution rates ranging from 0.54% to 22.34%. 4, 8, 3, and 9 significant SNP loci were detected for main root length, total root length, maximum root length, and lateral root length, respectively; 10, 7, and 1 significant SNP loci were detected for total root number, lateral root number, and adventitious root number, respectively; 14 SNP loci are associated with multiple root traits simultaneously. Twelve significant association sites are located within the known QTL (Quantitative trait loci) range of root related traits. A total of 49 root candidate genes were identified, among which GRMZM2G028386 (ABI4), GRMZM2G135713 (PUB23), GRMZM5G870592 (MYB98), GRMZM2G156861 (LOX1), GRMZM2G160005 (AUX16), GRMZM2G126936 (NAC2) and other important root candidate genes were identified. This study provides important reference for cloning genes related to maize root development and analyzing the molecular mechanisms of maize root development.