The sex pheromone of the obscure mealybug Pseudococcus viburni (Signoret) has recently been identified and synthesized. The objective of this study was to determine the relationship between pheromone-trap catches of male P. viburni with visual monitoring, and the usefulness of trap catches in predicting economic damage at harvest in table grapes. During the 2004-05 and 2005-06 seasons, pheromone-baited traps for P. viburni (25 µg racemic pheromone) were placed in vineyards in Chile’s central region. Male mealybugs were monitored from January 2005 until May 2006, and populations of mealybug nymphs and females were determined by 5 min counts per vine. Economic damage to fruit (infestation and severity level) was rated at harvest (0-3 scale). Trap catches of males at different dates (post-harvest of previous year, spring, and mid-season) were significantly correlated with 5 min counts in midseason. Also, male catches significantly correlated with damage at harvest, especially with infestation level (category ≥1) and the highest damage level (category 3). These results suggest that pheromone-baited traps are a promising technique for monitoring P. viburni in grapes, supporting findings for Planococcus ficus in California and South Africa.