Ambient particulate matter (PM) is increasingly recognized as an important pollutant because of the negative impacts on human and animal health. Primary PM emissions from agricultural activities need to be quantified in order to develop an agroenvironmental indicator that will better assess the contribution of the sector to the issue and the impact of mitigation measures. The contribution from crop harvesting operations to PM emissions is one of the emission factors not well documented. Measuring PM emissions from crop harvest is challenging because the combine acts as a moving point source rather than the usual stationary area source. In this study, the emissions of PM with aerodynamic diameter £ 10 mm (PM₁₀) from crop harvest were estimated using either an inverse dispersion model or a tracer technique. Using an algorithm in combination with the Industrial Source Complex (ISC3) model, the PM₁₀ emission rates during corn harvest was in the range of 0.4 - 2.8 g s^-1, or expressed in unit area 0.55-3.8 kg ha^-1. The difference in the estimated PM₁₀ emission rates for different days demonstrates the impact of environmental factors on PM emissions. For the tracer technique, the tracer gas was released from a point source moving along with the combine, and the ratio of tracer gas to PM₁₀ concentrations was then used to estimate PM₁₀ emission strength from the known release rate of tracer gas. The estimated PM₁₀ emissions from the tracer technique were also used to evaluate the performance of the algorithm used to estimate PM₁₀ emissions based on the inverse dispersion model.