This study was aimed to investigate the expression characteristics of two transcriptional factors in Ikaros family, Ikaros and Helios isoforms and their mechanism, as well as their correlation with clinical parameters, which play important roles in transcriptional regulation of hematopoiesis. Expression of Ikaros and Helios isoforms in a total of 163 patients with leukemia and correlations between Ikaros and Helios isoforms were analyzed by PCR. The results showed that different expression patters of Ikaros and Helios isoforms existed in leukemia patients, that is, Ikaros isoform (Ik-6) was predominantly expressed in acute lymphoblastic leukemia (ALL) with BCR/ABL fusion gene, while Helios isoform (He-i) was overexpressed in T-cell ALL patients. The results of cloning and sequencing demonstrated that the isoforms of Ikaros and Helios had different genetic alterations. The statistical correlation between these two isoforms not was found in this study, although interaction between Ikaros and Helios has been reported. It is concluded that although Ikaros and Helios belong to the same family with similar structure of zinc fingers, their isoforms have different expression profile, specific genetic alterations, and different clinical relevance in patients with leukemia. The connection and interaction between Ik-6 and He-i needs further research.