Chung, Y.S. Kim, G.D. Kwon, J.W. Lim, E.H. Woo, H.J. JACoW Publishing Geneva, Switzerland 2673-5350 978-3-95450-230-1 10.18429/JACoW-IBIC2021-MOOB03 English 13-15 linac MMI LEBT diagnostics instrumentation Contribution to a conference proceedings 2021 2021-10 https://doi.org/10.18429/JACoW-IBIC2021-MOOB03 https://jacow.org/ibic2021/papers/moob03.pdf RAON is a heavy ion accelerator for researches using Rare Isotopes (RI) as a major research facility in Korea. RAON uses both In-flight Fragmentation and Isotope Separation On-Line methods to provide various RI beams. The ultimate goal of the driver Linac of RAON is to accelerate uranium and proton beams up to 200 MeV/u and 600 MeV, with a maximum beam currents of 8.3 pA and 660 pA, respectively. After 9 years of RAON construction, commissioning of the low-energy Linac front-end system that consists of 14.5 GHz ion source, low energy beam transport, a 500 keV/u radio frequency quadrupole, and medium energy beam transport has been carried out since late 2020. And beam injection to the low-energy superconducting Linac is planned to start in December 2021. Here, we introduce RAON beam instrumentation and diagnostics systems as well as the construction status of the low-energy Linac.