Abstract: Quantitative studies of primary metabolites were conducted on healthy (control) and naturally infected (weakly, moderately and heavily) with Drechslera graminea, seeds and seedlings of Barley at different stages after sowing. Observations revealed that content of total sugars were highest in healthy (control) seeds and lowest in heavily infected seeds and were continuously increased in healthy (control), weakly and in moderately infected seedlings and decreased in heavily infected seedlings from 10 to 30 days after sowing. Total starch contents were also highest in healthy (control) and lowest in heavily infected seeds. Starch contents were slightly increased up to the 20 days and followed by deceased to the 30 days after sowing in all categories of naturally infected. Phenols and proteins decreased as the severity of infection increased and were highest in weakly infected and lowest in heavily infected seeds among naturally infected seeds. Total phenol contents were increased throughout from 10 to 30 days after germination. Proteins showed same response as phenols.