Xu, W. Fedotov, A.V. Hayes, T. Holmes, D. McIntyre, G.T. Mernick, K. Seberg, S.K. Severino, F. Smith, K.S. Than, R. Wu, Q. Xiao, B. P. Xin, T. Zaltsman, A. JACoW Publishing Geneva, Switzerland 2226-0366 978-3-95450-194-6 10.18429/JACoW-LINAC2018-MOPO004 English 40-43 MOPO004 cavity booster SRF gun MMI Contribution to a conference proceedings 2019 2019-01 https://doi.org/10.18429/JACoW-LINAC2018-MOPO004 http://jacow.org/linac2018/papers/mopo004.pdf One important component for LEReC project is a 704 MHz booster cavity, which was modified from the BNL ERL 704 MHz SRF gun cavity. The major modifications include converting the upstream cathode transportation to a proper beam pipe, adding a HOM coaxial line HOM damper to the downstream, retracting FPC insertions, and improvement of cryomodule layout. In the past one and half year, tremendous work was completed: the cavity was modified and tested vertically, FPC were conditioned, and HOM damper were designed and conditioned, cryomodule was re-assembled. The booster cavity cryomodule was successfully commissioned in mid October, and it was moved to LEReC location at RHIC tunnel 2 O’clock early November. This paper will report the configuration of the new cryomodule and its commissioning results.