Abstract: One hundred and seventy-two MYB transcription factors were extracted from the pepper genome database by bioinformatics methods，and there was a comprehensive analysis of the sequence characteristics，the chromosomal location，evolutionary relationships，protein conservative motif and genetic structure at the same time. What’s more，the technology of RNA-seq was used to screen MYB genes that might be related to the expression of spiciness genes. The results showed that there were 1R，2R（R2R3），3R，6R and other types of pepper MYB，among which R2R3 was the majority. Furthermore structural domain analysis showed that they have typical W type R2R3 conservative motifs. Subsequently，about twenty motif elements were obtained，and position analysis showed that MYB proteins from the same branch seem to have similar structural characteristics. A total of 37 groups were obtained through clustering with Arabidopsis thaliana，suggesting that the pepper MYBs may have various biological functions. The RNA-seq results indicated that the expression of twelve MYB，such as CaMYB98 and CaMYB168，were consistent with the accumulation of capsaicin content in fruit placenta tissues of‘Huangmowang’at different development stages. Thus it was predicted that they can regulate the metabolic pathwayof capsaicin by up- or down-regulating the expression of related proteins by binding to specific sites，which can be further studied as important candidate genes for the regulation of pungency.

Key words: Capsicum, MYB transcription factors, transcriptome sequencing, capsaicin content