Aim: SEM analysis of effect of chelating agent and endoactivator on smear layer removal from root canals of primary teeth. Material and Methods: Root canals of extracted human primary teeth were biomechanically prepared using 6% citric acid, endoactivator and normal saline, as control, for removal of smear layer .The specimens were subjected to scanning electron microscopic analysis. Results: In control group photomicrographs, debris and heavy smear layer covered the root canal surface and tubules in comparison to citric acid and endoactivator used study group photomicrographs which showed moderate to no smear layer on root canal surface and tubules. Conclusion: Effective removal of smear layer both by citric acid and endoactivator show promising use for root canals of primary teeth biomechanical preparation. Palabras clave: endoactivator, smear layer, citric acid, scanning electron microscope