Dosimetric comparison and evaluation of planning target volumes (PTV)  coverage and organs at risk  sparing using step and shoot (IMRT) and 3D CRT techniques for bladder cancer radiotherapy to evaluate the  dosimetric  parameters of the step and shoot (IMRT) technique, and compare them to that of the 3DCRT technique, and then to find whether the use of IMRT technique reduces homogeneity index or not. Data from 50 patients with bladder cancer, planned by IMRT and3DCRT were obtained. The prescribed dose for IMRT procedure and 3DCRT was (64 Gy). Also, the target coverage was achieved with 95% of the prescribed dose to 95% of the PTV in 3DCRT and 95% of the prescribed dose to 98% of the PTV in the IMRT plans. A total of fifty IMRT and 3DCRT plans were performed for evaluation of  dosimetric parameters (for each patient both treatment plans, step and shoot IMRT (6MV energy), and 3DCRT 10MVenergy) were done. This integral dose was calculated as the mean dose times the volume of the structure. The mean integral doses (ID) received by all the dosimetrically measured volumes and all of both the rectum, right and left femoral heads and small bowel were greater for 3DCRT than for IMRT shown in Dose- Volume Histogram (DVH).