In this study we show the correlation between the surface temperature of the water and its phytoplankton turbidity in Lake AL MASSIRA, from satellite data Landsat 7. To achieve that, we established thermal maps, from the thermal infrared band of Landsat data, illustrating the spatial distribution of the surface temperature of the lake. At the same time, we have created spatial distribution of phytoplankton turbidity maps of the lake; from the ratio between spectral bands (blue and red bands). The correlation study between the surface temperature and the phytoplankton turbidity factor shows a positive correlation coefficient of about of 0.802 (R2). The linear functions deduced from this correlation allow us to estimate and quantify the spatial distribution of living matter in water based on thermal infrared remote sensing data.