As fourth son of Erdeni Batur, founder of the Dzungar Khanate, Galdan was a descendant of Esen Taishi, the powerful Oirat Khan of the Northern Yuan dynasty who united all Mongols in the 15th century.

He backed his brother Sengge's claim to the title Khan of the Dzungars against the pretensions of their half-brothers Tsetsen and Tsodba Batur.

[2] After soundly defeating Tsetsen and Tsodba Batur in 1671, the Dalai Lama named Galdan Khong Tayiji "Crown Prince".

By the request of the latter, Galdan overthrew the Black Mountain Khoja [zh] in the Dzungar conquest of Altishahr and installed Afaq as his client ruler there.

[5] Then he invaded the north of Tengeri Mountain in modern Kazakhstan the next year; he defeated Tauke Khan's Kazakhs but failed to take Sayram.

To avenge the death of his brother and expand his influence over other Mongol areas, Galdan prepared for war with the Khalkha of eastern Mongolia.

Galdan established a friendly relationship with the Tsardom of Russia, which was at war with Tushiyetu Khan over territories near Lake Baikal in northern Khalkha.

In 1688, after two bloody battles with the Dzungar in present-day central Mongolia, Erdene Zuu Monastery and Tomor, Tushiyetu Khan and his son Galdandorji fled to the Ongi River.

After being reinforced by fresh troops, the Tushiyetu Khan Chakhundorji counterattacked the Zunghars, and fought with them near Olgoi Lake on August 3, 1688.

After a series of successful battles in the Khangai Mountains, at Lake Olgoi and Ulahui River, he approached the Great Wall of China.

On 12 June 1696, the same day Kangxi turned back, Galdan blundered into the western army and was disastrously defeated at Terelj's Zuunmod near the upper Tuul River east of Ulan Bator.

Failing in his objectives of usurping the Khaan's throne of Mongolia and the dreams of achieving greatness and with nowhere to go but facing imminent threat of being captured by the Manchus or Tsewang Rabtan, he killed himself by taking poison on 4 April 1697 in the Altai Mountains near Khovd with only 300 of his followers staying with him.

In 1698, Tsewang Araptan was forced to deliver the three of them to Beijing along with Galdan's ashes, which were then scattered on the military parade ground in the city.