The effect of spent engine oil pollution on some vegetative parameters of Eichhornia crassipes was studied in a greenhouse for eight (8) weeks to evaluate the level of tolerance of E. crassipes to spent engine oil pollution, and to make recommendations on the use of E. crassipes for phytoremediation of spilled engine oil. Three levels of spent engine oil: 5 ml, 15 ml and 45 ml were applied to pollute the water culture container. A plant grown in an unpolluted medium served as the control. Results showed that there were significant (p<0.05) reductions in plant height, width of lamina, leaf area and petiole length of all the plants in polluted media compared with the control. Among the treatments, 15 ml treatment had minimal pollution effect on plant growth and produced the highest percentage flowering whereas 45 ml treatment gave the highest pollution effect on the plant, resulting in low percentage flowering. The growth of the vegetative parameters of plants cultured in both polluted and unpolluted water was enhanced by the application of fertilizer. It is recommended that E. crassipes be employed in phytoremediation trial experiments since the vegetative parameters studied were not adversely affected by spent engine oil when supplied with nutrients like NPK fertilizer