Fusarium head blight (FHB) caused by Fusarium graminearum is responsible for billions of dollars in agriculture losses. The goal of the present study was evaluation the expression of acidic chitinase, one of PR proteins, in wheat defense response against different FHB induced treatments in 'Falat' as a highly susceptible and 'Sumai3' as a tolerant cultivar. These treatments contained fungi extract, spore suspension, DON and salicylic acid (SA). Infected spikes are sampled in 0, 3, 6, 12, 24, 36, 72 hours and 7 days after artificial inoculation and subjected to total RNA extraction and cDNA synthesis. Quantitative Real-Time PCR was performed with specific primer to detect expression differences between tolerant and susceptible cultivars. Output data was analysed using REST software, indicated differences in expression level of cultivars during the disease expansion cycle. These results support the emerging role of acidic chitinase gene in salicylic acid signaling pathway against necrotrophic fungal pathogen and demonstrate the effect of acidic chitinase gene in SAR signaling cascade against fungal extract treatment as PR protein inducer, as compare with these DON can’t act as a elicitor for acidic chitinase gene according to its expression profiling in this experiment. Results may serve as a foundation for dissecting mechanisms and regulations underlying FHB and SAR elicitors resistance reactions in wheat and revealing functions of the plant acidic chitinase gene in defense.