One of the major disadvantages of natural plant products as a biopesticide is due to its inconsistence pesticide effects. This in-vitro work aimed to observe the best dosage and consistency effect of essential oils of P. aduncum and C. flexuosus to P. palmivora. P. palmivora is a major obstacle of cocoa production in West Sumatra with disease percentage up to 40%. Activities were carried out at the laboratory of microbiology, Biology Department Andalas University in Padang and laboratory of plant protection of Bogor Research Institute for Spices and Medicinal Plants in Solok, both laboratories are in West Sumatra Indonesia. Research used completely randomized design (CRD) in a factorial with 10 treatments included control and three replications. The dosage of essential oils used were control, 250 ppm, 500 ppm and 1000 ppm. The best result was the mixture of these essential oils at the dosage of 1000 ppm due to its ability to control colony growth of P. palmivora to 100% and its fungicide consistency effect.