In the present work, diagnosis of deterioration of lithium greases used in rolling-element bearings by X-ray diffractometry (XRD), and analysis by X-ray fluorescence spectrometry (XRFS) and atomic absorption spectrophotometry (AAS) is reported. These techniques give reproducible reliable data to establish the severity of deterioration of greases recovered from the active zone of the bearings. XRD appears to be suitable to diagnose quickly the chemical changes occurred in the soap residue of the greases, available even in small quantity, compared to the other analytical and performance evaluation techniques. This paper gives diagnosis of the fresh lithium greases, chemical compositions and formation of new compounds in the greases after being used in the rolling-element bearings operated under the influence of electrical fields, and also under pure rolling friction without the effect of electrical fields on the roller bearing test rig. The deteriorated greases recovered from various motor bearings have als...