Abstract: 　Objectives　To explore the role of CD4⁺ T cell-derived leptin in peripheral blood mononuclear cells (PBMC) in asthmatic children. Methods Peripheral blood mononuclear cells were isolated from peripheral blood of both healthy subjects and asthmatic children in attack and remission stages. CD4⁺ T cells were purified from PBMCs by magnetic beads and were cultured in vitro. Supernatants were used to detect the levels of leptin by ELISA. The expression of the orphan nuclear receptor (ROR) γt was detected by real-time quantitative PCR (qRT-PCR) method. Results There was significant difference in CD4⁺ T cell-derived leptin levels of asthmatic children in attack stage (68.46±13.08 pg/ml), remission stage (36.73±6.13 pg/ml) and normal controls (32.82±5.79 pg/ml) (P<0.01). Through pairwise comparison, the leptin levels in children in attack stage were significantly higher than those in remission stage and normal control groups (P<0.01). But no statistical significance was found between remission stage group and normal controls (P>0.05). The plasma leptin of children in attack stage and remission stage, as well as in normal subjects were 16.64±3.53, 14.91±3.24 and 13.72±5.79 ng/ml respectively with no significant differences (P>0.05). The levels of RORγt mRNA were 0.341±0.175, 0.089±0.028 and 0.068±0.018 in children with asthma during attack stage, remission stage and in normal children respectively (P<0.01). Compared to remission and normal control groups, the RORγt mRNA level of children in attack stage was markedly higher (P<0.01), but there was no significant difference between asthmatic children in remission stage and the healthy controls (P>0.05). Furthermore, the result of this study showed CD4⁺T cell-derived leptin positively correlated to RORγt in asthmatic children in attack stage (r=0.681, P<0.01). Conclusions CD4⁺T cell-derived leptin is elevated in asthmatic children in attack stage and its level is closely related to the pathological process of asthma.