Objectives: Cephalometric radiographs are widely used in diagnosis and treatment planning. In the past, these radiographs used to be analyzed manually, but nowadays due to the possibility of errors and time-consuming nature of manual tracing, digital methods are replacing the manual methods. The reliability of computer-assisted analysis is of great importance. The purpose of this study was to investigate the inter and intra-rater reliability of 2D Dolphin imaging software version 10. 0. 00. 53. Methods: To assess the intra-rater reliability of lateral cephalometric analysis, 25 lateral cephalograms traced by one operator using Dolphin imaging software were traced again by the same examiner 2 weeks later. To assess the inter-rater reliability, 25 lateral cephalograms were traced independently by two examiners. Overall, 80 measurements including 43 linear, 34 angular, and 3 ratio measurements were made. The interclass correlation coefficient (ICC) was calculated to assess the inter-rater and intra-rater reliability. ICCs above 0. 75 were considered good. results: The ICC for intra-rater reliability was above 0. 75 for all parameters except lower vertical height depth ratio (ICC=0. 51), inter-labial gap (ICC=0. 54), superior sulcus depth (ICC=0. 67), articular angle (ICC=0. 733), and ramus height (ICC=0. 728). The ICC for inter-rater reliability was above 0. 75 for all parameters except nose prominence (ICC=0. 73). Conclusion: Dolphin imaging software showed good intra-rater reliability for most parameters and good inter-rater reliability for almost all parameters.