Abstract: In order to further understand the mechanism of the MYB gene family in the gene regulatory network, the MYB_DNA-binding conserved domain was used to screen 60 MYB gene family members from the protein sequences of Isochrysis galbana. Then, the protein (primary, secondary and tertiary) structure prediction and analysis, subcellular structure localization, gene structure, and conserved domains of these gene family members were analyzed. The results showed that: these MYB gene family members could be divided into three clusters, among which R2-MYB and R3-MYB were mainly concentrated in cluster 3, and R2R3-MYB contained most of the family members, indicating that these genes played an important biological function in Isochrysis galbana. The distant relationship between different branches and the close relationship within the same branch indicated that the MYB gene family in Isochrysis galbana had undergone some adaptive changes during the evolution process. Through the analysis of collinearity in the genome, the study found that there were 177 pairs of segmental duplication genes and 46 pairs of tandem duplication genes in the whole genome of Isochrysis galbana, among which there were 2 pairs of duplication genes in the MYB gene family, including the tandem duplicated gene pair IZ004267 and IZ007345, and the segmental duplicated gene pair IZ006462 and IZ006102. By combining with the analysis of chromosomal localization, IZ006462 and IZ006102 were located on chromosome 9, which also supported the above judgment of segmental duplication. The Ka/Ks values of these duplicated gene pairs were less than 1, indicating that these genes were subjected to gene purification selection during expansion and their functions were quite conserved.