Broad spectrum of different fungal pathogenic lifestyles can infect barley plants, most of which are responsible for significant annual crop losses. Understanding of gene expression that take place at the earliest stages of infection would be a necessary step for describing the initial mechanism between barley and the pathogen interactions. The purpose of the present work was to monitor the expression of some well-identified genes PR1, PR2, PR3,PR5, PAL and SGT1 during interaction of resistant barley plants with three economically important diseases viz. spot blotch (Cochliobolus sativus), scald (Rhynchosporium secalis) and powdery mildew (Blumeria graminis) at very early stages of disease development. Data demonstrated a remarkable contradiction in the gene expression patterns between barley and pathogens interactions 12 and 24 hours post inoculation (hpi), and all of them showed significant differential expressions compared to the control plants. The most significant differences were balanced in SGT1 expression which was 3.86 (C. sativus) and 2.5 (R. secalis and B. graminis) folds higher at 12 hpi as compared with the corresponding control treaments. The results revealed that barley plants activated various resistance mechanisms against the three pathogens 12 hpi and increased dramatically at 24 hpi, and the same defense-related genes expression were changed in adaptation to the each fungus. Overall, this work provides insight into a signaling pathway that accounts for classical gene expression changes at very early times of infection, elicited during barley interaction with fungal pathogens having various lifestyles.