Mango ("Mangifera indica") is a popular fruit and an important cash crop of southeast Asia. The mango malformation disease has been responsible for the degraded yield of the crop now for a long time (Kumar and Chakrabarti, 1997). The disease is difficult to cure and often takes the shape of an epidemic. Though much study has been done for the integrated control of the disease, the field implementations of the necessary technologies are difficult. This article describes a computerized expert system developed by the authors to help the agriculturists and the field scientists tackle the menace of the mango malformation disease.