Ten broiler flocks claimed to be suffering from aflatoxicosis in Ninavah governorate were subjected to study the correlation between natural contamination of feed samples with aflatoxin and European production efficiency factor (EPEF). Enzyme-linked immunosorbent assay (ELISA) method was adopted for estimation of AF level in broiler feeds. Growth performance parameters were recorded including final body weight, mortality, feed consumption and conversion ratio. Aflatoxins levels in feeds were ranged from 31 to 2381.8 ppb and EPEF was between 91.55-151.05. There was a highly negative correlation between AF concentration in broiler flock feeds and their EPEF (-0.828).