Human-system interfaces (HSIs) play an important role in enabling operators to communicate with the nuclear power plant (NPP) side. Getting the information required to understand a NPP's curren t status or perform necessary actions for responding to a given operational context are representati ve operator tasks performed using HSIs. To date, HSIs have been mainly evaluated in the context of human reliability analysis (HRA). However, the current HSI evaluation that occurs during HRA may be challengeable on two fronts: (1) reflecting the unique characteristics of HSI systems and ( 2) considering situations in which HSIs are poorly operated due to software/hardware malfunctions. Accordingly, this study proposes an approach for specifically evaluating HSIs for digital instrume ntation and controls (DI&C) systems, using Redundancy-guided Systems-theoretic Hazard Analys is (RESHA) and HRA. RESHA is a method for analyzing DI&C systems with redundancy feature s. In this study, we investigate how HSIs are evaluated in existing HRA methods, and what challen ges exist in the current approaches. To better evaluate HSIs for DI&C systems, this study modifies the existing HSI evaluation process by additionally modeling the HSI back-and front-ends. In thi s paper, a HSI fault tree for the APR1400 DI&C system is introduced through a piping and instru mentation diagram. It then touches upon what aspects of the suggested method must be further res earched.