Jiang Cheng's sister, Wei Wuxian's sworn sister. She's not too particularly beautiful but has a gentle and graceful personality, and really good culinary skills. Since young, she's been betrothed to Jin Zixuan, the young master of Lanling Jin clan. Treats Wei Wuxian like a brother. Underneath her gentle and polite exterior, however, Jiang Yanli was fiercely protective of her family. She refused to tolerate any insults towards her sworn brother Wei Wuxian, and she alone possessed the ability to reason with Wei Wuxian in the depths of his grief-stricken madness. Ultimately, she did not hesitate to sacrifice her life for her sworn brother's.
Jiang Yanli is in her late teenage years when Jiang Fengmian learns that Wei Wuxian has punched Jin Zixuan after the latter expressed his displeasure over their engagement. Jiang Fengmian convinces Jin Guangshan to cancel the contract, lest Jiang Yanli and Jin Zixuan find themselves in an unhappy marriage. Although she says nothing to Wei Wuxian at the time, he eventually realizes that she is quite dejected by the cancelation, as she is fond of Jin Zixuan.
Jiang Yanli is visiting her mother's relatives at the Meishan Yu Clan when Lotus Pier is massacred. After the Sunshot Campaign officially begins, she does what she can with her low cultivation, often preparing meals for the cultivators. When she accompanies Jiang Cheng and Wei Wuxian to assist the Lanling Jin Clan at Langya, she prepars three extra bowls of soup every night: one for Jiang Cheng, one for Wei Wuxian, and another for Jin Zixuan. Unfortunately, as she never leaves her name, Jin Zixuan is led to believe that another woman is responsible. When he encounters Jiang Yanli in his quarters, he accuses her of stealing another's credit, and Jiang Yanli bursts into tears. When Wei Wuxian finds her and exposes the truth, it takes the combined efforts of Jiang Cheng, Jin Guangshan, and Jiang Yanli to keep him from continuing to beat Jin Zixuan. Jiang Yanli then refuses to so much as look at Jin Zixuan for the rest of her time in Langya.
After the Sunshot Campaign, Jiang Yanli is typically found in the kitchen or the ancestral hall of Lotus Pier, as her brothers rarely visit the hall. Jiang Yanli is led to believe that Madam Jin invited her to the Lanling Jin Clan's night hunt on Phoenix Mountain. During the hunt, she finds herself alone with Jin Zixuan and insists that he does not have to feign interest in her. This irritates him, and when she attempts to walk away, he grabs her arm. Wei Wuxian and Lan Wangji interrupt, and Wei Wuxian again quarrels with Jin Zixuan.
Madam Jin soon arrives and threatens to beat her son for bullying Jiang Yanli, while Jin Zixun insults Wei Wuxian and accuses him of breaking a rule by taking one-third of the prey. Jiang Yanli promptly stands in front of Wei Wuxian. She initially apologizes to Jin Zixun for the fact that Wei Wuxian has upset him, before calmly turning the tables on Jin Zixun. She insists that Wei Wuxian is like a younger brother to her, that she will not accept insults against him, and that she has never heard of a rule against taking too much prey. She finishes her speech by demanding an apology from Jin Zixun, and, to his dismay, Madam Jin quickly supports her. As Jiang Yanli begins to walk away with Wei Wuxian, Jin Zixuan summons his courage to shout that he had been the one who wished to invite her, revealing that he has fallen for her after all.
Jin Zixuan eventually proposes, and Jiang Yanli accepts. She and Jiang Cheng sneak into Yiling to show the now-defected Wei Wuxian her wedding robes. Wei Wuxian eagerly eats the soup she has prepared as they talk. Jiang Yanli requests that he choose a courtesy name for her unborn son, and he suggests "Rulan." When Jin Ling is born, he is indeed given the courtesy name Rulan. Jiang Yanli is delighted at her son's fascination with his father's sword Suihua, and the couple happily declare that he will be a future swordsman. At her request, Jin Zixuan invites Wei Wuxian to their son's one-month celebration. However, when Jin Zixun uses the opportunity to attack Wei Wuxian on Qiongqi Path, Wei Wuxian loses control of his Demonic Cultivation, causing Wen Ning to kill Jin Zixuan and Jin Zixun by accident. Jiang Yanli accompanies the Lanling Jin Clan to the Pledge Conference at Nightless Sky, as all the clans disavow Wei Wuxian forever and plan to destroy the remnants of the Qishan Wen Clan he protects. As Wei Wuxian begins to fight them and raise corpses, Jiang Yanli runs through the crowd calling his name. By the time he finds her, a Fierce Corpse has risen behind her with a sword. As he panics, the corpse strikes her back. Lan Wangji cuts down the corpse, and Jiang Cheng holds the injured Jiang Yanli in his arms. Jiang Yanli expresses that she was here to see Wei Wuxian one more time, and convinces Wei Wuxian to stop the onslaught of corpses. As he begins to play Chenqing and the corpses begin to back down, Jiang Yanli suddenly sees a cultivator aim for Wei Wuxian. She pushes Wei Wuxian to the ground with explosive strength, and in the process, her own throat is run through with the sword.
Devastated by grief, Wei Wuxian brings the two halves of the Yin Tiger Tally together and commences the bloodbath of Nightless Sky.