Abstract: Fluted pumpkin (Telfairia occidentalis) is the foremost and most popular leafy vegetable in the diet of the inhabitants of Southeastern Nigeria, where its cultivation forms the economic mainstay of several families. Infection of the vegetable by Telfairia mosaic virus (TeMV) engendered severe mosaic, leaf distortion and malformation, rendering it unmarketable. In this study, the effects of TeMV on the chlorophyll content and photosynthetic capability of two ecotypes of T. occidentalis (herein referred to as ecotypes A and B) using nitrogen content as indicator were investigated. Chlorophyll contents were determined at 14, 30, 60, 90 and 120 days post inoculation (dpi) after extraction in 80% acetone, the supernatant filtered and values read spectrophotometrically. Nitrogen content was evaluated using the standard micro-Kjeldahl technique. Regarding the chlorophyll content, the results indicated that chlorophylls a, b and total chlorophyll were significantly reduced (p≤0.05) in both ecotypes A and B when compared to the controls at all growth stages. The results also showed a greater reduction of chl a than chl b in both ecotypes. The Nitrogen (N) content in both ecotypes were significantly reduced (p≤0.05) at all growth stages when compared to healthy controls. There were greater reductions in both chlorophyll and N contents in ecotype A than in B. The implication of the result is the inevitable loss in photosynthetic capabilities of both ecotypes with resultant poor vegetative growth and less economic returns.