Protein profiles of healthy and witches` broom (mycoplasma) infected jujube plants (Zizyphus jujuba) were investigated by 2-30% linear gradient polyacrylamide gel electrophoresis. Distinct differences in band patterns between healthy and infected samples were observed. Gels from samples of healthy leaves showed a characteristic protein band in the 50kd-range, which was not detected in infected leaves. Band with 25kd was more distinct in the infected leaves, whereas band with 198kd was more apparent in the healthy leaves. Healthy-looking leaves in the infected samples demonstrated the characteristic band of 50kd with less intensity showing intermediate pattern between healthy leaves and infected leaves. In contrast with leaf samples, gels from infected stem samples showed a characteristic band in the 335kd-range which was absent in healthy stem samples.