Inflorescence structure development determines the number of fruits and affects the size of fruits，which is one of the important agronomic traits of eggplant(Solanum melongena L.). Using eggplant single inflorescence material Z1-2 and raceme material 9712 as experimental parents，F2 generation extreme genetic segregation population was created after crossing and self-crossing，and single inflorescence extreme mixing pool，raceme extreme mixing pool, and parent pools were constructed respectively. Bulked segregant analysis sequencing(BSA-seq) method was used to resequence the whole genome of parents and extreme mixed ponds，and mapping of the single flower trait in eggplant was carried out to identify candidate genomic regions. At the same time，combined with RNA-seq data，candidate genes controlling single flower development of eggplant were mined. The results showed that the single inflorescence train in eggplant is a recessive qualitative trait controlled by a single major gene. Based on BSA-seq analysis，the major locus controlling single inflorescence traits of eggplant was mapped to chromosome 1，spanning a 5.25 Mb candidate region including 432 genes. Combined with transcriptome data analysis, six differentially expressed genes were identified within this interval. qRT-PCR analysis revealed that SMEL4_01g022100.1 and SMEL4_01g021830.1 were highly expressed in the buds of Z1-2, while SMEL4_01g022070.1 and SMEL4_01g022760.1 were highly expressed in the buds of 9712. The results provide theoretical basis for molecular marker-assisted selection breeding of eggplant single inflorescence and analyze the genetic mechanism of eggplant single inflorescence traits.