The present study aims to investigate the conservation of a wooden coffin of the sacred Ibis Mummy that dates back to the Greco-Roman Period. It was found in Minia excavations and transferred to the Grand Egyptian Museum in 2012 for conser-vation. For a better unders-tanding of deterioration and raising awareness of the conservation, many examinations and analyses were done, e.g. visual examination and documentation using AutoCAD (2D), optical microscope, X-ray Diffraction (XRD), and Infrared spectroscopy to define the type of wood, preparation layer, and binder. The coffin under study was kept in inappropriate conditions, causing further deterioration. Moreover, the surface decorations could be hardly seen because of the dust. After examination, conservation was conducted, including mechanical and chemical cleaning, installing friable painted gesso layers, filling cracks and pores, reassembling of the box and the lid, and adjusting the lid. The conservation was successful. Consequently, the coffin is ready for exhibition or storing.