Expert systems can serve as consultants who advise users as well asexpert assistants. One way to overcome and help detect oil palmdisease is by making an expert system as a medium of consultation onoil palm plantations so as to minimize the occurrence of disease attacksthat result in crop failure. The Shafer Dempster method is a reasoningmethod used to look for inconsistencies due to the addition orÂ subtraction of new facts that will change existing rules, enabling aÂ person to be safe in doing the work of an expert. Of 22 symptoms canÂ produce 5 diseases namely, stem base rot, rotting pupus, leaf canofy,Â bervak leaves and leaf rot. And the results of the calculation of theÂ dempster shafer process, resulted in a diagnosis of disease suffered byÂ oil palm crops with confidence values 0.80912 there is at the base of the stem, which is obtained from 6 symptoms that is G2, G4, G9, G14, G19, and G6. This expert system cannot be diagnosed ï± if theÂ diagnosis results and if the strongest confidence is found in more thanÂ one disease, the output produced by the system ie the system is unableÂ to display only one disease, the system will show the whole type ofÂ disease that has the same value big result of the calculation.