This study investigates the heat transfer characteristics of supercritical carbon dioxide (S-CO2) in a Z-shaped Printed Circuit Heat Exchangers (PCHE). S-CO2, with its abrupt thermophysical property variations near the pseudocritical point, poses unique challenges and advantages in PCHE design. A one-dimensional Segmental design method revealed that along the hot fluid flow direction, the local and total heat transfer coefficients increased, while logarithmic mean temperature and velocity decreased. Structural and operational parameters significantly influenced performance: heat transfer coefficients rose with higher cold-end flow rates, smaller hot-end hydraulic diameters, or reduced wall thickness, but declined with elevated hot-end inlet temperatures. These findings provide insights into S-CO₂ dynamic behavior in micro channel PCHE, guiding design improvements for compact, high-performance thermal systems.