The aim of this study is to perform threshold NDVI classification over a period of time to determine the condition of the vegetation in Ugwueme town which is influence by natural hydrocarbon seepage. To achieve this objective, three Landsat images, Landsat 7 TM+ 1996, Landsat 7 ETM+ 2006 and Landsat 8 OLI/TIRS 2016 were used to map the Landcover and monitor NDVI over the investigated areas. The classification analysis shows three vegetation cover classes which include Low class cover, Moderate

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... lass cover and High class cover, which were in increasing order of vegetation vigor. The result of the study shows that the category of high NDVI density reduces progressively from 36.81% in 1996 to 29.89% in 2006 and then to 23.12% in 2016. Similarly, the category of moderately NDVI density was also observed to reduce from 36.56% in 1996 to 28.25% in 2006 and then increase to 28.70% in 2016. In contrast to the high and moderate NDVI density category which were decreasing, the category of low NDVI density were visualize to increase from 26.63% in 1996 to 41.86% in 2006 and then to 48.18% in 2016. The study shows that sequel to natural hydrocarbon seepages in Ugwueme town, there was a general decrease in vegetation land cover indicating a trend of degradation of the ecosystem. Thus, afforestation and good land practices is recommended in the study area.