Abstract This work investigates the factors affecting the morphology of WC powder. WO3–C mixtures were prepared by high-energy ball milling and nano-sized WC powder was obtained in the form of platelets with a high aspect ratio (5–20) carbothermally. We observed that the WC powder contains excess (101) plane along with high level of strain during initial heating stage. Further, the temperature for the platelet formation coincides with that for the reduction of (101) peak intensity in the XRD pattern. From this study we found that the presence of excess (101) plane and high strain promoted the formation of platelet WC effectively.