This paper provides technical studies on the mural paintings of two remarkable temples in Upper Egypt; namely the temples of Seti I and Ramesses II. It is the first one in a series of studies investigating these mural paintings and their deterioration aspects. Therefore, this study deals with the techniques used in performing these mural paintings, and their stratigraphical structure. Visual and optical examinations, scanning electron microscope attached to energy dispersive X-ray spectrometer (SEM/EDS), and X-ray diffraction (XRD) analyses are the methods used in this respect. These methods revealed that the murals of the two temples are characterized by their variable materials and techniques. Firstly, the ancient artist carved the scenes, in some cases, directly on the stone and used in this sunk reliefs, raised reliefs, and a combination of them, while in others he applied a rendering layer on these reliefs. Also, in one case he applied the rendering on the wall without reliefs. Secondly, he used the tempera technique in all the paintings. Thirdly, both of limestone and sandstone were used as a support for the murals. The mortar sample was mainly composed of gypsum, lime and sand. All the rendering samples contained gypsum and lime with different amounts of sand, while just two samples showed the presence of clay in addition to gypsum and lime that were arranged in layers in a unique form.