ITER-India, as a part of its in-kind commitments to ITER project, has a mandate to deliver two “Gyrotron” based RF Source sets with state-of-the-art specifications (170 GHz, 1MW, 1000 s), for ECRH (Electron Cyclotron Resonance Heating) applications. With an aim to bench mark the integrated system performance, a MW class Gyrotron Test Facility has been developed at ITER-India under Phase-1 of the project execution plan. The facility has been developed with all necessary auxiliary systems and services such as the Low Voltage and High Voltage Power Supplies; Control, Protection and Monitoring Systems; RF Diagnostic Systems; Cooling and Vacuum Services etc. Further, a test Gyrotron with ITER relevant specifications (1MW, 170 GHz, 1000s) along with a set of dummy loads and waveguide components have been procured from M/s. Gycom, Russia, and fully integrated with the test facility. Detailed Site Acceptance Tests of the Test Gyrotron have been conducted at the newly developed ITER-India Gyrotron Test Facility (IIGTF). An output RF power of 1MW at 170 GHz for 1000 s with RF efficiency of about 50% has been successfully demonstrated during these tests there by validating the ITER relevant performance