In order to get uniform velocity distribution of airflow across the outlet, ventilation pipe structure of tea wind-driven insect-killing machine for tea garden was improved and optimized and the Reynolds-Averaged N–S equation in fluid mechanics, the Simple Algorithm for Flow and к–ε turbulence model were applied to calculate the numerical simulation model of ventilation pipeline using the Fluent software. With flow rate of the medium-pressure blower being 16 m3/min, the internal flow characteristics of ventilation pipe under no-load condition were obtained. Numerical analysis indicates when the distance between the two air inlets is 280 mm, the velocity distribution of airflow across the outlet is uniform.