Key words: rational application of physiological function, psychological function and color emotional tendency In modern society, color design is playing a role in more and more fields. From urban architecture to daily life, color is everywhere, and color is the first factor that affects the senses. When people observe objects, the visual nerve responds to colors the fastest, which is accompanied by the activities of other sensory organs and the brain, thus producing comprehensive perception and consciousness. Color affects people's lives quietly and affects people's mood subtly, so it is very important to design colors correctly in many fields. This paper will discuss the rational application of color perceptual tendency in interior design. When people use colors, they should not only rely on objective scientific knowledge, but also combine impressions, memories, associations, symbols, experiences and traditional habits to achieve the best color effect. The subjective feeling beyond these objective understandings is the perceptual tendency to color, which mainly includes the following aspects. First, color affects physiological functions. Different colors will cause different physiological reactions. Hungarian scientists have done experiments. They introduced blindfolded subjects into red, yellow and blue rooms respectively. As a result, after the subjects opened their eyes in the room, their pulse rates were "fast, normal and slow" respectively. As we all know, the color system can be roughly divided into two types: cold color system and warm color system. Long wavelength red light, orange light and yellow light give people a warm feeling. On the contrary, violet light, blue light and green light with shorter wavelengths give people the feeling of being cold. Cold colors and warm colors not only give people different feelings in temperature, but also bring some other feelings, such as weight, humidity, advance and retreat, etc. The physiological reaction caused by color does not come from physical reality, but is related to human visual and psychological association. Second, color affects psychological function. Kandinsky pointed out in On the Spirit of Art: "Generally speaking, color directly affects the spirit. Colors are like keys, eyes are like hammers, mind is like a piano full of strings, and artists are the hands playing the piano. It plays the keys purposefully, which makes people's spirit have all kinds of waves and repercussions. " People live in the world of color and have accumulated a lot of color vision experience. When the perceptual experience echoes the external color stimulus, it will trigger some emotions in people's minds, which is the perceptual tendency of color. Different colors can make people have different emotions and associations. For example, red gives people the feeling of enthusiasm, danger, vitality, joy and anger. Blue makes people feel calm, long-lasting, rational and fresh. Third, the emotional expression function of color Since color can affect people's physiology and psychology, different colors must have different emotional expressions. When applying, you must consider carefully and choose carefully according to the situation. For example, red is a traditional color in China, which means auspiciousness, happiness and warmth. Therefore, the interior design colors of wedding ceremonies, holiday feasts and other festive places are mainly red, and it is forbidden to use solemn colors such as black and cyan. Whether in China or in the west, the color of the bride's wedding dress is white, because white symbolizes purity, and the traditional red dress is also a common dress in Chinese weddings; However, the interior design color of funeral places is just the opposite, and there must be no bright colors of warm colors such as red, otherwise it is disrespectful. The emotional expression function of color is as follows. 1. Different people have different emotional needs for color. When planning the color of indoor space, we should fully consider the age, occupation, education, preferences and other specific conditions of the target group, and summarize the contents of users: Keywords: people who miss the dead wear black gauze, and mourning halls are generally decorated with white flowers and black gauze. In addition, different religions have different color symbols. Take yellow as an example. In Buddhism, yellow means humility and transcendence. In Christianity, yellow was once the color of Judah's clothes, so it has the symbolic meaning of meanness and betrayal. In interior design, we should respect the national customs and religious beliefs of space users and make full market research on the use of colors. 4. Different regions and environments have different emotional needs for colors. Due to objective factors such as geographical location and climatic conditions, people generally accept different colors. For example, people in tropical areas prefer strong and changeable colors, while people in cold areas prefer soft and calm colors. In rural areas, people have a soft spot for solid colors and contrasting colors, while in cities, people appreciate harmonious and elegant colors more. As far as the living room is concerned, the choice of indoor color should also be different because of its orientation. Generally speaking, if the doors and windows of the living room face south, sufficient sunshine makes the indoor color warm, so the color of the living room should be cool to balance the feeling of temperature; On the contrary, in a room with doors and windows facing north, warm colors should be used to raise the indoor temperature. To sum up, only by fully considering the geographical situation, national customs, religious orientation, personality characteristics, age, occupation and life experience of users can we design a space that really meets the needs of customers. Color can not only change people's visual understanding of known space, but also play its unique role in space. Therefore, we should follow some basic principles when designing indoor space. First of all, follow a harmonious system.