Yan Ying (c. 578–500 BC), better known as Yanzi, was a Chinese philosopher and minister of the state of Qi during China's Spring and Autumn period.

Yan Ying is written as 晏嬰 in traditional Chinese characters and as 晏婴 in modern simplified ones.

Some accounts of his diplomatic missions passed into Chinese folklore and proverbial sayings, although their exact historicity is uncertain.

When Yan Ying was mortally ill around the year 500 BC,[2] he had a letter sealed in a hole drilled in a pillar of his home, which he told his wife to ensure his son would read once he had grown.

In the fifth Chinese month of 548 BC, Duke Zhuang was killed by Cui Zhu's men for having an adulterous relationship with Tang Jiang.

Cui Zhu at the time was an extremely powerful minister of the state of Qi and detested Yan Ying.

As soon as Yan Ying heard the news, he stormed into the premises of Cui Zhu without guards and without any regard of his own safety.

In return, Duke Jing appointed Cui Zhu as the right prime minister and Qing Feng as the left.

[3] Prior to visiting the state of Chu, its leader King Ling wanted to humiliate Yan Ying.

Knowing that Yan Ying was short, the King instructed a smaller entrance to be made adjacent to the city gates.

After entering the city, the king met Yan Ying and asked conceitedly, "Is there no one else left in the state of Qi to send?

King Ling invited Yanzi to drink with him and, as they were happily discussing matters, two officers brought forth a criminal.

Yanzi rose from his seat and replied, "I have heard that the oranges to the south of the Huai River are large and sweet.

This story popularised the saying "southern oranges are bitter in the north" (南橘北枳, nán jú běi zhǐ).

[5] By the end of Yan Ying's visit, the king was so abashed that he is recorded as having personally accompanied Yanzi back home to Qi by way of apology.

To better gauge the situation of the state of Qi, the duke of Jin sent Fan Zhao, one of his senior officials, on a diplomatic mission.

Fan Zhao's use of the Duke's cup was a great disrespect to the state of Qi and it was a deliberate test to observe the reactions of his subjects.

Upon Fan Zhao's return to his state, he reported this incident to the duke of Jin and suggested that it was not the right time to invade Qi.

The Chinese idiom of "subduing the enemy with a wine vessel" (折衝樽俎, zhé chōng zūn zǔ) is based on this story and has the meaning of the importance of using diplomatic negotiations to avert war.

Confucius praised Yan Ying for his actions and stated that, "by upholding one's own wine vessel, enemies from thousands of miles away can be defeated".

Yan Ying knelt down to publicly denounced Zhu and said, "You were asked to take care of your majesty's birds, but yet you let one escape.

The affair of Yan Ying "killing three warriors with two peaches" (Chinese: 二桃殺三士, èr taó shā sān shì) comes from the Yanzi Annals.

The book Yanzi Chunqiu, compiled during the Warring States period (roughly 475–221 BC), includes stories of Yan Ying's advice to three Dukes of Qi and of his life and times.