High-entropy alloys (HEA) are novel materials obtained by introducing chemical disorder through mixing multiple-principal components, performing rather attractive features together with charming and exceptional properties in comparison with traditional alloys. However, the trade-off relationship is still present between strength and ductility in HEAs, significantly limiting the practical and wide application of HEAs. Moreover, the preparation of HEAs by trial-and-error method is time-consuming and resource-wasting, hindering the high-speed and high-quality development of HEAs. Herein, the primary objective of this work is to summarize the latest advancements in HEAs, focusing on methods for predicting phase structures and the factors influencing mechanical properties. Additionally, strengthening and toughening strategies for HEAs are highlighted, thus maximizing their application potential. Besides, challenges and future investigation direction of HEAs are also identified and proposed.