Long non-coding RNAs (lncRNAs) play various roles in gene regulation. GATA3 antisense RNA 1 (GATA3-AS1) is an lncRNA gene neighboring GATA binding protein 3 (GATA3). The current study aims to quantitatively compare the levels of the expression of GATA3-AS1, GATA3, and Interleukin-4 (IL-4) in peripheral blood mononuclear cells (PBMC) samples of MS patients and healthy individuals under the hypothesis of regulation of GATA3 and IL-4 expression orchestrated by GATA3-AS1. In this case-control study, the GATA3-AS1, GATA3 and IL-4 expression profiles were assessed using real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). Also, we assessed the IL-4 levels in the serum. The median fold changes in MS patients vs. controls were (4.39 ± 0.38 vs. 2.44 ± 0.20) for GATA3-AS1, (5.22 ± 0.51 vs. 2.86 ± 0.30) for GATA3, and (6.16 ± 0.52 vs. 3.57 ± 0.38) for IL-4, (P < 0.001). Furthermore, the mean serum levels of IL-4 were 30.85 ± 1.53 pg/ml in MS patients and 11.15 ± 4.23 pg/ml in healthy controls (P < 0.001). ROC curve analysis showed that the level of GATA3-AS1 might serve as a biomarker for diagnosing MS patients with the area under the curve (AUC = 0.918, P < 0.0001). Based on our results, this GATA3-AS1/GATA3/IL-4 pathway may increase IL-4 expression in MS patients. Our results indicate a probably regulatory function for GATA3-AS1and the levels of GATA3-AS1 in blood could be important biomarkers for MS diagnosis. To confirm and be more certain of these results, it is necessary to study neuromyelitis optica (NMO) and asthma patients in future studies.