To further increase the content of the ZrB2-SiC eutectic, the ZrB2-SiC powder fabricated by the raw materials with different particle sizes via induction plasma spheroidization process(IPS). The microstructure and phase composition of the corresponding coating before and after ablation test were investigated. The nanometer raw materials are beneficial to generate more ZrB2-SiC eutectic phases during the IPS process. The corresponding porosity percent of the coating also decreased from 32.26 % to 22.86 %. According to TEM results, the ZrB2-SiC coating contains two kinds of interstitial phase: fine ZrB2 particles surrounding by SiC and dendritic ZrB2-SiC eutectic, respectively. The ZrB2-SiC coating can effectively protect C/C composites for 120 s at 2000 °C with the ablation mass rate of −1.18 × 10−4 g/s.