The stored random samples of food seeds of wheat and rice (60 samples) were purchased from places of Eastern UP and Gurgaon district Haryana. Its moisture contents were estimated. The Mycological investigations of wheat seeds revealed presence of a total number of 16 fungal species viz.,Alternaria alternata,Aspergillus candidus,Aspergillus flavus,A. niger,A. ochraceous,A. phoenicis,A. tamari,A. terreus,A. sydowi,Fusarium moniliforme,F. oxysporum F. solani,P. glabrum,Rhizopus nigricans,Trichoderma virideandTrichothecium roseum.While mycological analysis of rice seeds showed presence of 15 fungal species viz.,Alternaria padwickii,A. oryzae,Curvularia lunata,Fusarium moniliforme,Aspergillus clavatus,A. flavus,A. niger,Cladosporiumsp.,Nigrospora oryzae,Alternaria tenuissima,Chaetomium globosum,F. solani,Microascus cirrosus,Helminthosporium oryzae,Pyricularia grisea. It also projected variation in presence of fungal species in blotter and agar plate method of analysis. In wheat Blotter method of analysis showed 16 fungal species while agar plate depicted 13 fungal species. In rice Agar plate method depicted presence of 15 fungal species while blotter method shows presence of 12 fungal species. The insect analysis revealed that wheat samples were infected withTribolium castaneum. While rice seeds sample showed presence of insectSitophilus oryzae. The investigations revealed thatAspergillus flavus,A. niger,Sitophilus oryzaeandTribolium castaneumcaused reduction in seed weight loss, seed germination, carbohydrate and protein contents of common food grains (wheat, rice). It also revealed that randomly selected A. flavus isolate 1 of wheat showed higher potential of aflatoxin B1production (1392.940 μg/l) while rice isolate 2 showed 1231.117 μg/l production.