Zijiao 子蟜 (d. 554), also called Gongsun Chai 公孫蠆, was a nobleman and minister in the state of Zheng 鄭 during the Spring and Autumn period 春秋 (770-5th cent. BCE). He was a son of Ziyan 子偃 and a grandson of Duke Mu 鄭穆公 (r. 627-606). He was a member of the house of You 游, one of the Seven Houses of Zheng (Qimu 七穆).
In 565, Zheng was attacked by the army of Chu 楚 under the command of Prime Minister (lingyin 令尹) Zinang 子囊 under the pretext of revenge for an earlier attack of Zheng against Cai 蔡. While the princes Zisi 子駟, Ziguo 子國, and Zi'er 子耳 suggested submission to Chu, Zikong 子孔, Zizhan 子展, and Zijiao proposed to ask the duke of Jin 晉 for help, but in the end, a peage agreement was made with Chu.
Yet in 564, King Gong of Chu 楚共王 (r. 591-560) attacked once more, and forced Zheng a second time to accept peace conditions, including the request to obey Chu, and not Jin.
A year later, a palace rebellion occurred against the powerful regent Zisi, and five noblemen led by Wei Zhi 尉止 killed high dignaries, among them Zisi, Ziguo, and Zi'er, kidnapped Duke Jian 鄭簡公 (r. 565-530), and barricaded themselves in the Northern palace (Beigong 北宫). Zijiao belonged to the group of valiant and loyal noblemen who, led by Zichan 子產 (d. 522, son of Ziguo), stormed the palace and killed the rebels.
In 559, King Zhufan 諸樊 (r. 560-548) of Wu 吳 was defeated by Chu, and asked other states for help. A huge number of representatives from many states promised Wu to launch a common punitive campaign. Zijiao was the representative of Zheng at the preparative covenant (meng 盟). In the same year, he travelled to Qi 戚, where several states promised to pacify the internal rebellion of Sun Wenzi 孫文子 and Ning Huizi 寧惠子 in Wei 衛.
An allied army of several countries launched an attack on Qin 秦 in the year. Zijiao led the contingent of Zheng, but the campaign yielded no victory. In 556, Zijiao retired, but a year later, he participated in Duke Jian's campaign against Qi. He died in 554 as a highly honoured person not just in Zheng, but also in Jin.