In this study, TRIP 800 (transformation induced plasticity) steel plates having 1.5 mm thickness were joined by copper-based (CuAl8) wire in gas metal arc brazing technique. Specimens were prepared in joining forms as butt joint. Brazing operations were done with five different shielding gas flow rates of 8, 10, 12, 14, and 16 L/min. CuAl8 wire composed mostly of copper serves as the filler metal. Having accomplished the brazing operations, tensile properties of joints were detected, and micro- and macrostructures of joints were investigated in order to see the joinability of TRIP 800 steel by gas metal arc brazing technique.