The superconducting linear accelerator serves as the injector of HIAF, pre-accelerating ion beams from the ion source. For example, the 238U35+ beam can be accelerated up to 17 MeV/u. After acceleration, the beam will be delivered either to the low-energy experimental terminals or to the synchrotron BRing. The iLinac consists of a continuous-wave RFQ, a medium-energy beam transport line (MEBT), and a superconducting linac operating at 2 K, incorporating both quarter-wave resonator (QWR) and half-wave resonator (HWR) cavities.