Aim: aim was to analyze and compare the accuracy of two impression techniques. Materials and Methods. An extracted first molar, was prepared by standard method for full crowns with processed preparation finish line of 1 mm depth and convergence angle of 3–4∘ . Impression was made 20 times with one–stage technique and 20 times with two–stage technique using an appropriate tray. The distance between the restoration margin and preparation finish line of plaster dies was vertically determined in mid mesial, distal, buccal, and lingual (MDBL) regions by a stereomicroscope using a standard method. Results. The results of independent test showed that the mean value of the marginal gap obtained by one stage impression technique was higher than that of two–stage impression technique. Conclusion. The findings of the present study indicated higher accuracy for two–stage impression technique than for the one–stage impression technique.