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Introduction IMRT is recognized as a powerful technique to improve quality of dose distribution in head and neck (HN) radiotherapy. Purpose To compare Constant and Variable Dose Rate VMAT (CDR,VDR respectively) to Step-and-Shoot IMRT (SS CDR and VDR plans consisted of two 6 MV arcs (182° to 178°; clockwise and counterclockwise direction). All plans were performed with Pinnacle3 TPS (v 9.8). Dose distributions were compared by evaluating PTVs’ D mean , D 2% , D 50% , D 98% and Homogeneity Index (HI); for MA, SC, BS D 2% ; for PA, SG, ES, LA and TH D mean and a number of different dose-volume data in V 20 Gy – V 50 Gy range. To compare efficiency, MUs and treatment delivery time were evaluated. Results Concerning PTVs coverage, all techniques were equivalent although VMAT ones significantly improved HI and decreased D 2% . For OARs significantly better results were found for VMAT techniques with reduction in the volume of LA, TH and ES receiving medium and high doses. Compared with S&S-IMRT, VMAT techniques reduced delivery times although MUs were higher. Conclusion VMAT techniques offer better results and CDR is an additional option of rotational arc radiotherapy for linacs without variable dose rate with a lower cost.