Abstract Chemical analysis of pheromone gland extracts followed by behavioural studies in the wind tunnel and by field trapping tests show that the sex pheromone of the Guatemalan potato moth, Tecia ( Scrobipalpopsis ) solanivora Povolny (Lepidoptera: Gelechiidae), is a blend of (E)‐3‐dodecenyl acetate, (Z)‐3‐dodecenyl acetate, and dodecyl acetate. A 100 : 1 : 20 blend of these compounds, formulated at 1000 µg on rubber septa, captured more males than the main compound alone. This lure was species‐specific and did not capture the potato tubermoth, Phthorimaea operculella . A potato field was treated with a blend of these three compounds at a rate of 28 g ha −1 . Male T. solanivora attraction to synthetic pheromone traps was almost completely suppressed for 2 months, demonstrating the potential use of pheromones for control of this economically important insect pest of potato in Central and Southern America.