Objectives: assessment of the accuracy of linear measurements in maxilla obtained by CBCT scanner (Planmeca Promax 3D MID CBCT machine and software) in comparison with the real measurement obtained from the dry skullsMethods: - The study was performed on thirty (30) dry skulls obtained from the Anatomy Department of Faculty of medicine, Cairo University. The skulls attached to their mandiles were radiographed using Planmeca ProMax 3D Mid CBCT machine. Real measurements were performed using a digital caliper. The results obtained was subjected to Intra- and inter-observer agreement was assessed using Intra-Class Correlation Coefficient (ICC).Bland-Altman plot (differences-vs-means plot) used to show the agreement between two quantitative measurements by studying the mean difference and constructing limits of agreement .Results: excellent correlation was shown between the maxillary CBCT linear measurements and real measurement obtained from dry skulls. There was excellent inter and inter observer reliability. Conclusion:-Maxillary linear measurements driven from CBCT images of Planameca Promax 3D Mid® machine are accurate, reproducible and reliable for all maxillofacial applications.