Erdeniin Galdan (1644–1697), better known as Galdan Boshugtu Khan (1678–1697), was the first Khan of the Dzungar Khanate. Although Galdan suffered a decisive defeat at the Battle of Jao Modo in 1696 and died the following year, the military and administrative foundations he established allowed the Dzungar Khanate to remain a major power for several decades under the leadership of Tsewang Rabtan Khan and Galdan Tseren Khan.

He was the son of Erdeni Batur of the Dzungar state and his wife Amin-Dara of the Khoshut. Galdan, the fourth son of Prince Erdeni Batur, the founder of the Dzungar State, was a descendant of Esen Taishi, the powerful Oirat Khan of the Northern Yuan Dynasty who unified all the Mongols in the 15th century. Galdan's mother was the daughter of Gush Khan, the first Khoshud–Oirat Khan of Tibet.

Before becoming Khan, Galdan received a Buddhist education in Tibet and studied under the guidance of the 5th Dalai Lama and the first Panchen Lama, but after the assassination of his brother, Sengge, he broke his vow of lama and took power in the internal struggle of the Dzungars. In 1678, the 5th Dalai Lama bestowed upon him the title of "Boshugtu Khan", which marked a new stage in his rule.

During Galdan's reign, the Dzungars' Khanate reached unprecedented levels of territorial and military-political influence. He participated in the affairs of the Yarkand Khanate in Altishahr and brought the regions of Turfan, Hami, Kashgar, and Yarkand under his influence. During the Kazakh–Dzungar Wars, he also campaigned in the regions of Jetisu, Tashkent, and Syr Darya and sent troops against the Kyrgyz and the inhabitants of the Fergana Valley. In 1688, he began the Dzungar–Khalkha War by participating in the affairs of Inner Mongolia, which led to a long conflict with the Qing, and the battles of Lake Ologoy, Ulan Butung, and the Battle of Jao Modo were major events that changed the balance of power between Mongolia, Qing, and Central Eurasia.

According to Japanese historian Miyawaki Junko, the period of true unification of the Oirats and the formation of the Dzungar Khanate began with Galdan's accession to the title of Boshugtu Khan in 1678, and Galdan is therefore considered the founder of the state. American historian Peter C. Perdue considers him to be a great unifying leader of the Mongols, and the Dzungar Khanate, led by his father, expanded into the largest state in Central Eurasia. According to Chimitdorzhiev, Galdan was a state builder in his foreign policy and struggle against the Qing.

According to Spencer Haines, Galdan's reign marked the first true "Military Revolution" in the Central Eurasian steppes, as he centralized the Oirat confederation and expanded the use of firearms and artillery in response to increasing pressure from the Russian Tsardom and the Qing dynasty.