The ability to harmonize the color of the restoration with the natural tooth is an important factor in determining the success of the restoration. However, color remains the primary clinical problem to date. The nature of color is the electromagnetic spectrum, and the human eye is able to respond to color perception at different wavelengths from 380-780nm, and the color perception process includes physical-physiological-psychological stages. The human eye has different ability to perceive the three characteristics of color: lightness, hue, and color change. Because the cone cells that perceive color are mainly concentrated in a small area in the center of the retina, and the rod cells that perceive luminance are distributed in a large area around the retina, the human eye has the most sensitive perception of luminance. In dental color control, the luminance value is the first element, followed by the saturation value, and the hue value has the least influence on the reproduction of dental color. In the color space, the perceptible tooth color difference caused by a unit difference in lightness value is equivalent to the color difference caused by two saturation values or three deviations in hue values. Of the four elements of shape, color, quality and translucency, the aesthetics of the restoration is largely determined by the latter three. The color of the tooth is not pure white, its basic shade is yellow or orange, only the color saturation is lighter, thus giving the impression of white. Teeth are divided from the outside into enamel, dentin and pulp. The enamel is translucent and colorless, and the color of the tooth is the combined color of the inner dentin and pulp through the enamel. Clinically, the doctor chooses the tooth color based on many factors. Generally speaking, white skin tone can choose a whiter tooth color, women’s teeth are generally a little whiter than men’s. As we age, the surface enamel wears away and exogenous or endogenous pigmentation increases, the color of the teeth will become darker. Of course, the color of the teeth is not the whiter the better, otherwise it will give a very fake feeling, commonly known as “denture face”, which is against the principle of aesthetics. The basic principle of aesthetic restoration of teeth is health and harmony, which involves not only the color of the teeth but also the morphology, translucency, surface texture, gingival aesthetics and other factors. The color of the restoration should be compatible with the patient’s skin tone, gender and age. The ideal result is to harmonize the color with the rest of the natural teeth in the mouth to achieve the effect of falseness. Of course, different patients may have their own special color requirements, and the doctor will consider the individual needs of the patient in addition to the medical principles when selecting the color, and doctor-patient communication is essential. In order to obtain the ideal color for a restoration, various aspects are involved, including color comparison (color comparison or color selection), transmission of color information between the doctor and the dental technician, reproduction of the tooth color pattern with restorative materials, color evaluation, etc. Therefore, a science called dental colorimetry has been developed for the color of teeth, which covers various aspects of color fundamentals, tooth color measurement, tooth color materials, colorimetric techniques, color information transfer, color reproduction, and color evaluation. As far as colorimetry is concerned, it is the basis for restorative work. Color selection methods include visual colorimetry and instrumental colorimetry. Instrumental colorimetry in color reproduction, between the medical-technical ultimately need a physical medium (color film or color scale) as a reference, the restoration of the evaluator is human, must ultimately be based on visual color. Visual colorimetry is simple and easy, and is the most commonly used clinical technique, but there are many influencing factors and accuracy is affected to a certain extent; instrumental colorimetry is not affected by subjective and environmental factors, and is highly accurate and reproducible, but the operation is complicated, the corresponding clinical cost is high, and the popularity is not high. Visual colorimetry includes several key aspects: the object to be compared, color standards, lighting and environmental conditions, the observer, etc.. A comprehensive consideration of all influencing factors is required to achieve clinically accurate colorimetry in dentistry, thus laying the foundation for the reproduction of restoration color. The visual colorimetric method is performed using colorimetric plates. The classical 16-color colorimetric plate has a clinical color matching rate of less than 30% due to its own design deficiencies. The colorimetric plate and other designs based on dental color space and color theory, the accuracy of colorimetric than the classic colorimetric plate greatly improved, the clinical color matching rate can reach 70-80%. Therefore, if possible, it is better to use new colorimetric plates and matching porcelain powder to improve the clinical color and aesthetic effect. It is best to take intraoral digital video together with the colorimetric film and transmit the digital photos to the technician via the Internet for simulation reproduction reference. The colorimetric film can only convey color information, but other more important information such as individual characteristics, translucency, surface characteristics, etc. can be conveyed by means of photographs. The colorimetric film is digitally photographed together with the natural tooth and marked to maximize the information conveyed to the technician such as individual characteristics, semi-transparency, surface characteristics, etc. The correct transfer of the colorimetric results to the technician for color reproduction is an important aspect of dental color. The correct method of recording and transmitting information: according to the complexity of the tooth color, the zonal recording method can be used: 3 zones, 5 zones, 9 zones, indefinite zones, and additional digital photos to assist in transmitting information. During the colorimetric process, the communication and information feedback between doctors and patients, medical technology is especially important.