ZrB2 is one of the most promising materials for extreme environment applications, especially in the aerospace field, due to the combination of superior thermophysical properties and low density. Nevertheless, pure ZrB2 is intrinsically hard to sinter, requiring either the application of intense external pressure or the use of sintering aids. In the present work, the feasibility of ultrafast high-temperature sintering (UHS) for the densification of commercial ZrB2 was explored. Thanks to the addition of B4C as a sintering aid, Densities up to 92-98% could be obtained in just 2 min. Hardness of 16.3-17.8 GPa was obtained for the UHS ZrB2-based ceramics, similar to what is reported in the literature using slower, more sophisticated and energy-consuming sintering approaches like spark plasma sintering. These first results show that UHS could provide a quick and simple way to produce high-performance ZrB2-based components with just a few minutes of processing time in pressure-less conditions.