Herein, we report on the in situ reactive synthesis and simultaneous densification of a high-purity ternary Zr3Al3C5 phase via pulse electric current sintering (PECS) of Zr/Al/graphite powder mixtures with a molar ratio of 3:3.2:4.8. The phases and microstructure evolution in the 580 degrees C-1800 degrees C temperature range were characterized by X-ray diffraction, real-time sintering curves, and a scanning electron microscope equipped with an energy dispersive spectroscope. An additive-free, fully dense Zr3Al3C5 compound was obtained at 1800 degrees C using a load corresponding to a stress of 35MPa for 20min. The final product was comprised of 96.61wt% Zr3Al3C5, 3.14wt% ZrC, and 0.25wt% Zr2Al3C4; the relative density was 97%.