Exosomes are extracellular vesicles that are involved in intracellular communication and different biological processes. Recently, the importance of microRNAs (miRNAs) in exosomes has been considered as biomarkers in asthma diagnosis. This study aimed to determine the expression of selective miRNAs from plasma-derived exosomes in moderate and severe asthmatic patients compared with healthy controls. Forty-six subjects including 22 patients with severe and mild to moderate allergic asthma and 24 healthy controls have entered this study. MiRNAs were extracted from the plasma exosomes and selective miRNAs (miR-21, miR-16, miR-Let7, miR-148a, miR-155, miR-125, miR-150, miR-146a, miR-223, miR-126) expressions levels were determined; using quantitative polymerase chain reaction (qPCR). In this study, we found a significant up-regulation of miR-223 and miR-21 in moderate asthmatic patients compared to the healthy controls (p=0.002, p=0.006). MiR-223 and miR-21 had the probability of 83% and 76% diagnosis estimation in moderate asthmatic patients respectively. Therefore, they could be used as biomarkers in these patients.  No expression of miR-125, miR-126, and miR-155 was found in plasma exosomes by qPCR in this study. The other miRNAs had no significant expression between different groups. Based on our findings,miR-223 and miR-21 may be considered biomarkers or used for targeted immunotherapies in asthma.