The Aschiagar () is a river of Mangystau Region of Kazakhstan and runs some to the east of the city of Aktau.
The river is long and drains a basin of about . The source of the Aschiagara is located on the southern slopes of Karatau, north of the town of Kuryk. The width of the bed ranges from , and the depth is .
The average annual water flow at the mouth about , and in April during snow melt there has been an increase in flood levels by on average. The river freezes in mid-December and begins to thaw in early March.