The present work has been carried out mainly to determine the effect of lead on the growth and cell organelles of Carrot (Daucus carota L.) callus. 1 mM of lead nitrate is added to the culture media R-2 and callus cells are cultured for 16 days. The growth rate is measured by fresh weight and structural changes of cell organelles is observed by electron microscope at every 4 days. The results show that lead inhibits the growth of Carrot callus and disturbs the structure of mitochondria remarkably.