Abstract: In present study effect of Mungbean yellow mosaic virus on the chlorophyll, total nitrogen, protein, total phosphorous and carbohydrate content in three varieties of mungbean plants HUM -2 (Malviya Jagriti), ML-192, Pusa Baisakhi were studied. Total chlorophyll, chlorophyll a, chlorophyll b content and carbohydrate content were lower in virus infected mungbean plant varieties. Total nitrogen, protein increased and total phosphorous content was found to be high in virus infected mungbean leaves. Estimation of chlorophyll in healthy and diseased leaves of mungbean plants at 15, 30, 45, 60 and 75 days were done and absorbance were recorded by spectrophotometer at 663 and 645 nm. Total nitrogen of leaves was measured by modified microkjekldahl method and total protein content was determined by multiplying the total nitrogen content with 6.25. Total phosphorous were estimated by digestion with Tri-acid mixture and reading was taken in spectrophotometer at 470 nm. Determination of carbohydrates were done by total water soluble sugars and starch content.