The goal of the current study was To compare different radiotherapy planning techniques for gastric cancer and impact of advance techniques on dose to OAR ( Organ at Risk ) . Materials and Methods A total of 20 gastric cancer patients were involved in current study and each patient was scheduled IMRT and VMAT techniques. Dose-volume histogram statistics, conformal index (CI), hand monitor units (MUs) were analyzed to compare treatment plans, treatment planning system eclipse Algorithm AXB with Energy true beam linear accelerator Varian model Results and Discussion The VMAT plans exceeded the IMRT technique for coverage planning tumor volume dose and reduction dose for organs at risk in the kidneys, but not in the liver. VMAT exhibited a better mean CI ( 0.89±0.03), than the other techniques. In addition, for the kidneys the dose sparing (V13, V18 and mean kidney dose) was improved by VMAT plans. However, IMRT showed a marginal advantage in V30 and mean dose in normal liver when compared with VMAT. The conclusion of this study suggest that VMAT provides improved tumor coverage when compared with IMRT, VMAT haven't no advantage in liver protection when compared with IMRT.