Cytoplasmic male sterility (CMS) was one of the important ways to create hybrid by using heterosis in Brassica napus. The selection of restorer line and the study of restorer gene was helpful to improve the application value of CMS line. In this study, we used the cytoplasmic male sterile line 1193A and restorer line 15R1 of Brassica napus as parents to construct a hybrid pool of two extreme characters in F₂ population. The restorer gene was located and analyzed by BSAseq technology. The results showed that： (1) 33 883 nonsynonymous SNPs between 1193A and 15R1, and 7 996 nonsynonymous coding mutations between mixed pools were obtained . (2) The results of indel detection and annotation showed that there were 2 918 mutations between parents and 840 mutations between mixed pools. (3) Based on the correlation analysis of SNP and indel, the restorer gene was located in the 0-880000 region of C09 chromosome, with a total length of 880 kb. (4) Through the SNP and indel annotation of candidate regions, we found that there were 40 SNPs with nonsynonymous mutations between parents, 65 SNPs with nonsynonymous mutations between mixed pools, 7 indels with frame shifting mutations between parents and 11 indels with frame shifting mutations between mixed pools. The coding genes in the candidate region were annotated. The results showed that 162 genes were annotated, including 11 nonsynonymous mutations and 5 frame shifting mutations. These genes may be related to fertility restoration.