(NH4)(2)HPO4 is widely used in industrial product as a typical additive. To reveal the inhibition of (NH4)(2)HPO4 on the wheat dust explosion, a vertical pipeline was built to study the explosion of wheat dust with different particle size distribution under the addition of (NH4)(2)HPO4. The characteristics of wheat dust explosion were recorded by high-speed photography, ion probe and micro-thermocouple. The pyrolysis behaviors of wheat dust and (NH4)(2)HPO4 were investigated by simultaneous thermal analyzer, and the explosion residues were characterized by FTIR and XPS. The results indicate that the flame propagation distance, velocity and temperature were significantly decreased under 25% (NH4)(2)HPO4, and the wheat dust explosion was significantly inhibited. In the explosion reaction zone, the ion current increases and then decreases with the content of (NH4)(2)HPO4 increases. Furthermore, the inhibition mechanism of (NH4)(2)HPO4 on wheat dust explosion was presented by analyzing the samples and residues of wheat dust explosion. (C) 2020 Elsevier B.V. All rights reserved.