Lighting refers to the application of light sources and the use of different light effects in the environment to create a certain atmosphere. It is a very important factor in designing a healthy, comfortable and successful living and working environment. Lighting can affect people's behavior, mood, sense of security, as well as sense of space in a certain environment. Different lighting effects can bring different atmospheres, and its importance in architecture design and home decoration should not be ignored. In terms of architecture design, adequate lighting can create a sense of symmetry, hierarchy and focus. In terms of home decoration, carefully planned lighting can be used to enhance the beauty of a home and make it aesthetically pleasing. When it comes to specific lighting, there are interior lighting and exterior lighting. Interior lighting is mainly used for indoor activities of the human body, to create a comfortable, non-glare light to protect the visual comfort of the people in the environment. Exterior lighting is mainly used to beautify the city, bring people a visual enjoyment, highlight the attractive features of tourist attractions, and also provide light for walking and driving. In conclusion, lighting plays an important role in the design and decoration of architecture and homes. Proper planning and combination of different lighting types will bring beautiful and comfortable atmospheres for living.