Earthworms are important soil organisms involved in organic matter decomposition, nutrient cycling, soil aeration and maintenance of soil fertility. The present study compares the effects of the chemical fertilizer urea and the organic fertilizer Kala Sona on the survival, biomass, length, activity and morphology of Eisenia foetida, together with histological examination of the clitellum region. Two experimental setups were conducted using different fertilizer concentrations and an untreated control. In the first setup, the project reported increasing mortality with increasing urea concentration, including 60% mortality at 1.5 g/kg after 20 days. In the second setup, 1.5 g/kg urea was reported as harmful and 3.0 g/kg as lethal by the trial-and-error procedure described in the project. Kala Sona-treated groups generally showed better survival, activity and biomass.