Thymus and activation-regulated chemokine (TARC) is a keychemokine for attracting Th2 lymphocytes into sites of allergicinflammation. The aim of this case-controlled observational study is todetermine the plasma TARC level in asthmatic children and its relation toasthma severity and atopic markers. Forty four asthmatic children aged 6months to 5 years (30.6 ± 15.9 month) and a control group of 21 matchedhealthy children were recruited for the present study. Plasma TARClevels were significantly higher in asthmatic children (956.2 ± 330.7pg/ml) than controls (212.1 ± 90.9 pg/ml) p < 0.0001. Levels were alsosignificantly higher among patients with moderate persistent asthma(1240.9 ± 299 pg/ml) as compared to those with mild persistent (902 ±193 pg/ml) and intermittent asthma (690.5 ± 155.2 pg/ml) p < 0.0001. Asignificant positive correlation was also demonstrated between TARClevel and markers of atopy such as total serum IgE level. Our resultssupport the notion that TARC is mechanistically involved in asthmapathophysiology and its plasma level can be used as a biomarker toidentify and monitor asthma severity.