In the process of high-speed additive manufacturing, machining defects such as low surface accuracy, high surface roughness, residual stresses and micro-cracks have a serious impact on the performance and life of the product. These machining defects need to be removed by post-treatment in order to promote the use of additive manufactured parts in industrial production. This article provides a systematic review of existing post-treatment technologies for additive manufactured parts, divided into surface post-treatment technologies and overall post-treatment technologies. The processing cost expenditure of the most common post-processing methods is analyzed. The core values and key metrics of post-processing are explored. The prospects for post-processing technology for additive manufactured parts in six key development directions are discussed. The present review systematically discusses the process capabilities and research developments of post-processing technologies for high-speed additive manufacturing, taking into account knowledge from both basic and applied research areas.