Abstract: With the rapid advancement of photovoltaic(PV) power generation technology, the performance optimization of PV inverters, as the core power conversion equipment, has become a focal point in the industry. Current research primarily focuses on enhancing power quality, with innovative breakthroughs in harmonic suppression technology driving the continuous expansion of inverter applications. By incorporating advanced intelligent algorithms, inverter technology has achieved a leap from traditional modulation methods to intelligent modulation strategies. This not only meets the stringent requirements of modern power systems for high-efficiency power conversion, but also significantly improves the system's low harmonic output characteristics and intelligent control capabilities. The fundamental architecture of PV inverters is systematically elaborated and the primary mechanisms of harmonic generation in inverters are thoroughly analyzed. Based on the technical characteristics of harmonic suppression methods, these are categorized into two main approaches: source suppression and propagation blocking. The former focuses on reducing harmonic generation, while the latter emphasizes innovative applications of filtering technology. Through a systematic review of improvements in existing harmonic suppression technologies, the key technical challenges in the field of harmonic suppression are discussed and a forward-looking analysis of future development trends in harmonic suppression technology for PV inverters is provided, offering theoretical references and technical guidance for related research areas.