The effect of Y2O3 additive on the nitridation of diamond wire silicon cutting waste (DWSCW) was studied by using X‐ray diffraction, thermo gravimetry, differential thermal analysis, scanning electron microscope equipped with energy‐dispersive spectrometry, and an equivalent alternative method, and the individual particles of DWSCW were simulated using cubic polycrystalline silicon blocks. The results showed that the native SiO2 film on the surface of DWSCW can be disrupted at low temperature (1300°C) by adding Y2O3 additive, which provide good channels for the diffusion of SiO and N2 and improve the overall conversion of DWSCW. Y2O3 additive can also reduce the initial nitriding temperature of cutting waste, change the nitriding kinetic behavior, and promote the formation of β‐Si3N4 through accelerating the nitridation of cutting waste at high temperature (≥1500°C). In addition, when 8 wt% Y2O3 additive is added to the cutting waste, the complete nitridation is achieved, at 1350°C, and ωα + ωβ reaches a maximum of 83.6 wt%.