Bronchial asthma (abbreviated as asthma) lacks a particularly effective treatment. Mesenchymal stem cells (MSCs) have been widely studied in the field of asthma treatment for their roles in inhibiting inflammation and improving airway remodeling, as well as their advantages in respiratory tract administration. In recent years, although the exploration of MSCs on the treatment of asthma has been surging, the results of the clinical trials are not satisfactory. The differences in types of stem cells and pathophysiological characteristics of asthma patients have posed serious challenges to the clinical application of MSCs. This article reviews the current studies on the mechanism and clinical application challenges of MSCs in the treatment of asthma, so as to better understand the therapeutic potential and clinical feasibility of MSCs.