【Objective】In Arabidopsis, MYBL2 negatively regulates the biosynthesis of anthocyanins and proanthocyanidins. The MYBL2 genes from six Brassica species with different leaf colors were cloned. By analyzing the sequence and expression pattern of MYBL2, the function of MYBL2 in the biosynthesis of anthocyanins in Brassica species was explored. 【Method】The sequences of MYBL2 from the six Brassica species with different leaf colors were obtained using homology-based cloning method and multi sequence alignment and phylogenetic tree analysis were performed. The purple leaf materials of B. rapa, B. napus, B. juncea and B. carinata were treated with shading, and the expression level of MYBL2 gene was analyzed by transcriptome sequencing and qRT-PCR. The qRT-PCR in B. oleracea, B. napus, B. juncea and B. carinata with purple and green leaves were also performed to evaluate the expression level of MYBL2. Based on the nucleotide variation sites of the cloned MYBL2-1 and MYBL2-2 sequences, PCR markers which could distinguish the genomic origin of alleles were developed. 【Result】A total of 56 copies of 9 homologs of MYBL2-1 and MYBL2-2 were cloned from 19 samples of six species of Brassica. The BcaMYBL2-1 gene was obtained for the first time. The total length of BcaMYBL2-1 sequence was 867 bp, including two introns of 168 bp and 102 bp respectively, encoding 198 amino acids, with a molecular weight of 22.69 kD and an isoelectric point (pI) of 8.72. Sequence alignment and evolutionary analysis showed that BcaMYBL2-1 was derived from B genome. Among the MYBL2-1 and MYBL2-2 copies of six species in Brassica, only BraA07.MYBL2-1, BolC06.MYBL2-1 and BcaMYBL2-1 exhibited sequence differences in different leaf color materials. After shading treatment, the leaf color of purple leaf material becomes lighter than that of the unshaded part. In Chinese cabbage Zibao 5, the expression of BraA07.MYBL2-1 and BraA02.MYBL2-2 in the shaded part were 0.7 and 0.4 times of that in the unshaded part, respectively. In Brassica napus with purple leaves and white flowers, the expression of BnaA07.MYBL2-1, BnaC06.MYBL2-1, BnaA02.MYBL2-2 and BnaC02.MYBL2-2 in the shaded part were 0.4, 0.5, 0.4 and 0.4 times of that in the unshared part, respectively. In purple leaf mustard, the expression of BjuA07.MYBL2-1, BjuB03.MYBL2-1, BjuA02.MYBL2-2 and BjuB05.MYBL2-2 in the shaded part were 0.4, 0.3, 0.4 and 0.2 times of that in the unshared part, respectively. In B. carinata with purple leaf, the expression of BcaMYBL2-1, BcaB03.MYBL2-1 and BcaC03.MYBL2-2 in the shaded part were 0.3, 0.4 and 0.5 times of that in the unshared part, respectively. However, the expression of BcaB05.MYBL2-2 in the shaded part was 2.4 times of that in the unshared part. Comparing the expression of MYBL2 gene in different leaf color materials of Brassica, the results showed that the expression of most of the homologous genes of MYBL2 gene in purple leaf materials was higher than that in green leaf materials except kale. In kale, the expression of BolC06.MYBL2-1 and BolC02.MYBL2-2 in green kale were 2.5 and 3.5 times that in purple kale, respectively. In Brassica napus, the expression of BnaA07.MYBL2-1, BnaC06.MYBL2-1 and BnaC02.MYBL2-2 in purple leaf and white flower were 7.5, 8.6 and 26.0 times of that in green leaf and white flower, while the expression of BnaA02.MYBL2-2 in green leaf and white flower was 13.0 times of that in purple leaf and white flower. The expression levels of BjuA07.MYBL2-1, BjuB03.MYBL2-1, BjuA02.MYBL2-2 and BjuB05.MYBL2-2 in Brassica juncea were 8.3 times, 11.8 times, 23.2 times and 14.6 times of those in Sichuan yellow respectively. In B. carinata with purple leaf, BcaMYBL2-1 and BcaB03.MYBL2-1 were 7.1 and 27.6 times as much as W-BCDH76, respectively. However, BcaB05.MYBL2-2 and BcaC03.MYBL2-2 genes of W-BCDH76 were 2.8 and 5.0 times as much as those of B. carinata with purple leaf, respectively. Five pairs of primers were obtained, which can effectively identify the MYBL2 from A, B and C genomes of Brassica. 【Conclusion】After shading treatment, MYBL2 gene expression was closely related to light. The regulation mechanism of MYBL2 gene in Brassica plants involved in anthocyanin biosynthesis was different from that of Arabidopsis plants in which MYBL2 gene negatively regulated anthocyanin biosynthesis.