Young Hopeful Geyser is a geyser in the Lower Geyser Basin of Yellowstone National Park in the United States.
Young Hopeful Geyser is part of the Black Warrior Group which includes Artesia Geyser, Gray Bulger Geyser, and Steady Geyser. Young Hopeful is a collection of several vents which, depending on the seasonal water table, erupt either continuously or intermittently. The vent nearest Firehole Lake have gone dormant while the ones near the boardwalk trail have become more active. The two largest vents often reach about 2 feet (0.61 m) but sometimes surge to 6 feet (1.8 m).