The Predynastic Zhou or Proto-Zhou (/dʒoʊ/; Chinese: 先周) refers to the ancient Chinese state ruled by the Ji clan that existed in the Guanzhong region (modern central Shaanxi province) during the Shang dynasty, before its rebellion and subsequent conquest of the Shang in 1046-1045 BC led to the establishment of the Zhou dynasty. According to histories, predynastic Zhou rose as a western frontier vassal state of the Shang, acting as its ally against the Xirong barbarians until their influence surpassed that of the Shang dynasty.
Records about predynastic Zhou came from two sources. The Shang dynasty kept records about Zhou in oracle bones. The texts about Zhou inscribed by the Shang court are mainly those from the reign of Wu Ding and the last Shang monarchs. After the fall of Shang, the Ji clan established the Zhou dynasty and started their own narrative about previous generations. The Book of Documents and the Bamboo Annals are two major historical sources. Later, Sima Qian wrote about the country using those texts as reference.