Abstract: Traditional CAD systems generally rely on tedious manual operations in the design process, which often leads to low efficiency and error accumulation. This experience and rule-based design approach not only limits innovation capabilities, but also extends the design cycle and increases costs. In recent years, the introduction of artificial intelligence technology has brought about a new revolution in CAD. Through deep learning, pattern recognition, and data-driven new algorithm models, intelligent CAD systems can achieve automated CAD data generation, real-time error detection and correction, and demonstrate unprecedented levels of intelligence in design optimization, parameter adjustment, and even achieve good results in tasks that were previously difficult to complete, such as CAD reconstruction. This article provides an overview of the research on the integration of artificial intelligence and CAD. Firstly, it introduces commonly used datasets in the CAD field. Then, it summarizes the changes that artificial intelligence has brought to the CAD design process from three aspects: CAD representation, forward engineering, and reverse engineering. Finally, it explores the driving role of the rapidly developing Large Language Model (LLM) in CAD design in recent years. Finally, it summarizes the current research status of intelligent CAD, discusses future development trends, and attempts to propose some directions that can be optimized.