Closed-loop Argon Power Cycle (APC) engines fueled by hydrogen combine a high heat-capacity ratio (¿ ˜ 1.65 compared with 1.40 for air) with the potential for thermal efficiencies exceeding 60 % and near-zero emissions. In this concept, argon replaces air as the working fluid while oxygen and hydrogen are injected separately. The exhaust stream is routed to a condenser where water is removed and the argon is recirculated to the engine intake, creating a nearly closed mass balance. Whether turbocharging is feasible for APC engines given the altered gas properties and temperature constraints remains a critical design question. Turbocharging could recover part of the exhaust energy via the turbine instead of rejecting it entirely in the condenser, but its viability must be quantified before hardware selection. This study presents a two-stage framework for evaluating turbocharging in a hydrogen-fueled closed-loop APC operated with a heavy-duty marine engine. First, an analytical feasibility metric based on turbomachinery energy balances for argon is developed to determine the minimum exhaust temperature and overall turbocharger efficiency to achieve a positive boost-to-backpressure pressure difference. Second, an air-based turbocharger map representative of a six- cylinder medium-speed marine-class engine is scaled to APC conditions using similarity and gas-property corrections for flow and speed. The results indicate that an exhaust temperature of 700K combined with an overall turbocharger efficiency of 50% enables a boost-to-backpressure ratio of unity, given compressor pressure ratio of 2:1. Turbocharging provides an efficiency enhancement of up to 2 percentage points at full load, consistent with pumping-loss magnitudes reported in literature.  However, turbocharging is only feasible at medium to high loads and elevated exhaust temperatures, and its impact on engine thermal loading under argon-rich conditions warrants a dedicated investigation.