Tibetan hulless barley (Hordeum vulgare L. var. nudum) is one of the primary crops cultivated in the mountains of Tibet suffering from low temperature, high salinity, and drought. Specifically, drought is one of the major abiotic stresses that affect and limit Tibetan barley growth. Thus, it's critical to explore the molecular mechanism of hulless barley during arid or drought environmental conditions for improving crop yield. Here, we employed quantitative proteomics by data-independent acquisition mass spectrometry (DIA-MS) to investigate protein expression in tolerant (XL) and sensitive (DQ) cultivars.