Background and aim: One of the dentists' problems is the identification of proximal caries. B.W. radiograph is the most traditional method that is used in proximal caries detection. Another method can be used caries identification (especially in proximal caries) is the using of digital system that carry out by traditional scanner& digital camera. Its aim in vitro study was the comparison between the diagnostic power of conventional and digitized radiographs in detecting proximal caries.Methods and Materials: 40 extracted molars were selected. Cavities were prepared by 1/2 round bur D& Z under contact point. Then cavities were become deeper and larger by 1, 2, 3 & 4 round burs on 40 proximal surfaces of dentals. B.W. radiographs were taken and digitized by a digital camera"DSC-W200Sony cyber- Shot with 6, 9, 12 Mp. The conventional and digitized radiographs were observed by 4 experienced radiologists.Results: The mean of sensitivity in B.W. method is 97.5%, the mean of specificity is 91.25%, in detection by digital camera with resolution 6Mp the mean of sensitivity is 98.125%, the mean of specificity is 88.75%, with resolution9Mp the mean of sensitivity and specificity are 95.75%, 91.25% respectively; with resolution 12Mp, the mean of sensitivity and specificity are 98.75%, 92.5%. No significant differences were showed between them.Conclusion: This study showed, digital camera can be used for digitizing conventional radiographs, saving in computer, observing when ever and sending to a far place.