Stephanie of Milly (died c. 1197) was lady of Oultrejordain and an influential figure in the Kingdom of Jerusalem.

She was the daughter of Philip of Milly, lord of Nablus, and was the granddaughter of Maurice, lord of Oultrejordain. Through her various marriages she became lady of Oultrejordain. Her first marriage, in 1163, was to Humphrey III of Toron , who died in 1173. Her son with Humphrey was the future Humphrey IV of Toron. Her second husband was Miles of Plancy, lord of Oultrejordain, who was assassinated in 1174. In 1176 she married Raynald of Chatillon, the former prince of Antioch, who had recently been released from captivity in Aleppo.

In 1183 Stephanie's son Humphrey married Isabella of Jerusalem in the castle of Kerak, but the ceremonies were interrupted by the arrival of Saladin, who besieged the place. Stephanie sent messengers (and, supposedly, a piece of cake) to Saladin, reminding him of the friendship they shared when he had been a prisoner in Kerak many years before. Saladin did not lift the siege but agreed not to target Humphrey and Isabella's wedding chamber. (The siege was soon raised by king Baldwin IV of Jerusalem, Isabella's brother.)

Through Stephanie, Raynald inherited the lordship of Oultrejordain, and used his new position to harass Muslim caravan and pilgrimage routes; at one point he threatened to attack Mecca itself. This led to the invasion of the kingdom by Saladin in 1187. Raynald was killed at the ensuing Battle of Hattin, and Humphrey IV was later captured. Saladin agreed to return Humphrey to Stephanie in exchange for Kerak and Montreal; the castles refused to surrender, however, and Stephanie dutifully sent her son back to captivity under Saladin. (Saladin took pity on her and released him.)

After Raynald's death she married Hugh III Embracio, who died in 1196. In 1197 she accompanied an army to besiege Jubail, and bribed a guard to open up the city to them. She seems to have died soon after this.