The potential of using the castor oil was investigated for control of papaya diseases caused by the fungi Colletotrichum gloeosporioides and the bacteria Pseudomonas caricapapayae.The fungistatic activities of the castor bean essential oil and constituents were evaluated via the poisoned food technique as described by Suberu (2004) with some modifications. Antibacterial activity of castor bean oil was determined using the disc diffusion assay as described by Wilkinson and Cavanagh (2005). Purified castor bean essential oil used in this study was purchased from TALGO (São Paulo/Brazil).Treatment with 1% castor oil did not significantly affect the fungal growth. The efficacy of castor oil for control of anthracnose increase when 5% and 10% were used in assays resulting in significant reduction of mycelial growth. Treatment of fruits with 5% aqueous emulsions resulted in significant reduction of pathogen spread in fruits treated. No lesions were founded in treated fruits, in contrast to control. Castor oil have no significant effect against bacteria P. caricapapayae when tested using standard disc diffusion assays at 10%, 50% and 100% of oil. These results suggest the potential use of the castor bean essential oil and fatty acids constituents for the control of anthracnose diseases in papaya fruits.