The growth periods are essential for the formation of soybean yield and seed-quality traits, as well as for the ecological adaptability of soybean varieties. Thus, the mining of genetic loci and candidate genes for growth periods is important to dissect its genetic basis in soybean breeding. In view of this, 300 soybean accessions were used to analyze ten growth period related traits under two environments. Furthermore, the genome-wide association study (GWAS) was conducted by combining with 5.38 millions of SNPs of these accessions. The results showed that there existed abundant genetic variations of these ten growth period related traits (R1 to R8, RP and R/V) in the accessions, with the coefficients of variations (CV) ranged from 7.3% to 36.0%, and the largest CV appeared in R/V. Meanwhile, the results also showed that there existed significant correlations among these growth period related traits, which implying the existences of pleiotropic genetic loci. Moreover, a total of 2070 stable and pleiotropic associated SNPs were detected with at least two traits or under at least two environments. These SNPs located on 18 chromosomes (except chromosome 5 and chromosome 12), with the largest number of associated SNPs (62.8%) detected on chromosome 10, followed by chromosome 6 and chromosome 9. Furthermore, a lots of pleiotropic genetic loci for the growth periods were discovered, such as Gm16:27911126-Gm16:29624572 on chromosome 16 (nine traits, R1 to R8 and RV), Gm10:44591107-Gm10:46521535 on chromosome 10 (seven traits, R3 to R8 and RP), Gm09:40595870-Gm09:40691399 on chromosome 9 (six traits, R1, R2 and R4 to R7), and Gm15:4961358-Gm15:6102837 on chromosome 15 (six traits, R1 to R6). Additionally, some candidate genes were screened out in the associated loci, including the known function gene E2 and some newly discovered candidate genes, such as Glyma.10G218100. The results provided novel genetic loci and candidate genes for growth period improvements in soybean breeding.