This study measured the impact of extension on cocoa production in Idanre and Ile-Oluji Local Government Areas of Ondo State. Data were collected from two sets of cocoa farmers: those visited by extension workers (FV) and those not visited (FNV). The selection procedure was random and multistage. Data were collected by means of a pre-tested structured interview schedule and analyzed by means of both descriptive and inferential statistics. The finding of the study showed that farmers visited by extension workers recorded higher outputs (2.5 tonnes on the average) than those not visited by extension workers (1.13 tonnes) and, within FV group, the highest outputs were recorded by farmers who had highest frequency of contacts with extension workers. These findings suggest that extension can help to close the gap between the outputs attainable with existing technologies and those actually realized by farmers.