The sterilization of organic objects using Carbon dioxide is one of the safest methods which used in conservation of organic materials which eliminates the presence of insects and other aerobic organisms. The fumigation process with Carbon dioxide takes two to three weeks and requires a high levels of carbon dioxide “more than 60% (no matter how high the rate of the oxygen). This study explains this sterilization method and evaluates the effectiveness of the method on the pigments and colors of an ancient Egyptian painted wooden ushabti-box, from the collection of the Egyptian museum of Tahrir to insure if it is safe and has no negative effect. Different analyses techniques have been used such MicroscopicExamination for Identification of ancient wooden box, X-ray florescence (XRF) for Identification of Egyptian pigments, Change of color by spectrophotometer, in addition Visual Assessment, Documentation Process by High Resolution Camera, Scanner in Multispectral Imaging(MSI),MultiSpectral Imaging(VIS-UV-IR)and X-RayRadiography have been applied for documentation procedures, also Isolation and identification of micro- organisms. The results showed that the wooden Ushabti box depicts on the top a falcon squatting on a cartouche Dates back to Late Period dynasties which highly carved and decorated. It has a layer of Pigments: Yellow, Green, Blue, Red and Black. Microscopic Examination revealed that the wood was sycamore. X-Ray Florescence Spectrometry (XRF) showedthattheblackpigmenthastheelementCarbon;theYellowpigment hastheelements calcium, iron, and arsenic. Change of color by spectrophotometer indicates that CO₂ has no effect on the pigments.This study proved from the recorded values that the sterilization process by using carbon dioxide does not affect or change the degrees of colors in which indicate that CO₂ has no effect on the pigments on the archaeological wooden box.