In this article, the influence of some key operating parameters on the drying behavior of the Attarat oil shale deposit in the central region of Jordan have been investigated using two different techniques: a thermogravimetric analyzer (TGA) and a standard drying furnace. The weight loss and drying rates of oil shale samples were measured gravimetrically. It was noticed that the drying rate falls off at a critical temperature of approximately 140C and becomes almost zero beyond this temperature. For all examined samples, the surface moisture loss was found to be proportional to the drying temperature: the higher the temperature the more free water can be driven off. Under isothermal conditions, larger grain size of oil shale particles witnessed lower rates of moisture loss. Such results are in agreement with published work, but for different oil shales. It may be concluded, from this experimental investigation, that natural drying of oil shale particles at normal temperatures will not be effective. But when the temperature is raised by means of special solar collectors or concentrators, it would be possible.