The aim of this study was to evaluate the ability of an Argon laser to eliminate the smear layer after root canal preparation. Thirty three freshly extracted teeth were selected. The working length was established 1.5/2mm short of the apical foramen. The root canals were cleaned and shaped up to a minimum of 30 K file at the working length and flared using a step back technique. Between each file a 2 ml of NaOCl as irrigant was delivered and a final irrigation was conducted. A 300 micrometers fiber was introduced in each root canal, in a wet mood until the working length and the fiber was working in each canal for two times. Each pulse duration was 0.02 sec. and interval between each pulse was 0.2 sec. Five groups of six teeth were selected regarding power delivered: 2W, 1.5W., 1W., 0.75W., 0.5W. plus a group control unlased. Samples were then fixed and prepared for SEM examination and the evaluation of the smear layer removal was conducted using an image analysis system.