The Warring States period (simplified Chinese: 战国时代; traditional Chinese: 戰國時代; pinyin: Zhànguó Shídài), also known as the Era of Warring States, is a period in ancient China following the Spring and Autumn period and concluding with the victory of the state of Qin in 221 BC, creating a unified China under the Qin Dynasty. Different scholars use dates for the beginning of the period ranging between 481 BC and 403 BC, but Sima Qian's date of 475 BC is most often cited. Most of this period coincides with the second half of the Eastern Zhou Dynasty, although the Chinese sovereign (king of Zhou) was merely a figurehead.

The name of the period was derived from the Record of the Warring States, a work compiled early in the Han Dynasty.