The in vitro antifungal effect of five essential oils (EOs) (EO1, EO2, EO3, EO4 and EO5) extracted from Lippia origanoides, L. citriodora and L. alba on isolates of Monilia (Moniliophthora roreri] was evaluated. Lippia plants were collected at five locations in Colombia, and monilia isolates were obtained from infected cocoa fruits collected in San Vicente de Chucuri, Santander, Colombia. The fungi strains (Ml, M2, M3, M4 and M5) were characterized by morphology, germination and growth in culture media. Antifungal activity of different concentrations of EOs was evaluated against the M2 and the isolated strain of M. roreri (ATCC 64239) determining their effect on germination and mycelial growth inhibi- used at concentrations from 800 to 1000 ?g/ml. Concentrations of 200 ?g/ml also showed an effect on fungal isolates, being the EOs obtained from L. origanoides (EO2 and EO3) the most active. These were mainly composed of thymol, p-cymene, -terpinene, timilo acetate, carvacrol, -myrcene, trans- fungal strains studied, being generally more susceptible the isolated M2 that the ATCC strain. The EOs of L. origanoides are candidates for use as biofungicides possible to control the moniliasis. Future studies oriented to determinate the in vivo antifungal activity of these EOs and its major components are required.