In this study, four-pod mutants of soybean were used as materials for the first time to sequence and analyze the transcriptome of unpollinated ovary with Illumina/Solexa technology. The results showed that 55 582 genes and 2 060 differentially expressed genes（DEGs） were obtained by sequencing, of which 1 381 were up regulated and 75 were DEGs with log2 ratio greater than 10. The analysis of significant enrichment of GO and KEGG showed that the differential genes were almost involved in the metabolism, transcription, translation and signal transduction of all major substances, such as sugar, fat, amino acids and hormones. The sequencing results will lay a foundation for the cloning of four-pod related genes and the study of molecular regulation mechanism, and also have important theoretical significance for the cultivation of new soybean varieties by molecular biological means in the future.