Erwinia sp. have been long known as plant pathogens that produce a wide range of enzymes able to degrade plant cell wall components [8,9]. Leu et al. [10] reported that Erwinia cypripedii caused black rot on seedlings, trees and fruits of papaya in Taiwan. In 1982, Trujillo and Schroth reported two diseases. Erwinia decline of papaya (D strains) and the Erwinia mushy canker disease of papaya (MC strains), in Hawaii [11]. Webb [12] reported a species of Erwinia that caused angular water-soaked lesions on leaves and firm water-soaked cankers on the stems of papaya. Recently, the causal agent of bacterial canker in papaya was identified as a new bacterium species named E. papayae [5]. In this 1μm study, we report for the first time E. mallotivora as a new pathogen of papaya. The disease is transmitted from plant to plant or to other parts of the same plants, primarily by insects, birds, humans and rain splash [4,13]. Bacteria may enter through stomata, hydathodes, and lenticals and through wounds made by, for example, insects and hailstorms. From the leaf, the bacteria pass into the petiole and the stem, first colonizing and then moving through vessels of the plant.