The development of three dimensional conformal radiotherapy (3D-CRT), in which the high-dose volume matches the target volume and avoids normal tissues, has been a major theme for improving the physical basis of radiotherapy. Intensity modulated radiation therapy (IMRT) is the most advanced form of 3D-CRT. As with medical imaging, its development requires the professional activity of physicists and engineers. This study carried out in Ayadi Almostkbal Oncology Center – Alexandria, Egypt. All Dosimetric measurements were carried on siemens linear accelerator (ARTISTE) which produces photons with energy 6 and 10 MV. This study aimed to carrying out dosimetric and verification measurements for applying intensity modulated radiation therapy (IMRT) technique on oncology patients. Dosimetry involves more than accounting for delivered dose. It involves ensuring that the MLC shapes are accurate and are correctly assigned to the patient.Any changes in shaping must be correctly and accurately incorporated into the field sequence. The information system should be implemented in a way that ensures good quality assurance practices.