In collaboration with ANSALDO, ENEA is performing a design and manufacturing feasibility study for the first wall of NET during the physics operation phase. The main design specifications are the average neutron wall load = 1 MW/m 2, peak surface heat flux = 0.4 MW/m 2, total number of bum pluses = 1×10 4, average burn pulse duration = 100 s, structure material = ss 316L S.A., coolant = H 2O (He) at 50 °C. The ENEA-ANSALDO (reference design is based on the use of flat plates coupled by nicrobrazing to water poloidal cooling tubes. The final aim of the work is manufacturing a representative NET first wall box segment (mockup of indicative dimensions 0.65×0.25×0.15 m 3) suitable for testing in the 190 kW Thermal Fatigue Test Facility at JRC-Ispra. In this paper we report on the related design work and the results of the studied performed: technological development (manufacturing test activity, brazed joints characterization tests, mockup design and manufacturing), thermomechanical analysis, plasma-wall interaction studies (tests on protective carbon composite material, theory), and tritium transport analysis.