Hualālai is a dormant shield volcano on the island of Hawaiʻi in the Hawaiian Islands. Its peak is 8,271 ft (2,521 m) above sea level. Hualālai is one of five volcanoes on Hawaii island and it lies roughly due west of the saddle between the much higher volcanoes Mauna Kea and Mauna Loa. Hualālai forms the backdrop to the town of Kailua-Kona, which is built on the southwestern slope of this mountain, where most Kona coffee is grown.

Hualālai is built from a well-defined rift zone that trends approximately N50°W across its summit and a less well-defined rift zone that trends northward from a point 3 miles east of the summit. The oldest dated rocks on the mountain's surface are about 128,000 years old. Hualalai grew above sea level approximately 300,000 years ago and is in the post-shield stage of its development.

Over 100 cinder and spatter cones are arranged along the rift zones. There is no summit caldera, although there is a collapse crater (~ 0.3 mile across) at the top of a small lava shield. Much of the southern slope (above the town of Kailua-Kona) consists of lava flows covered by a layer of volcanic ash from 10 cm (a few inches) to a meter (3 ft) thick. The last eruption of Hualalai was in 1800-1801 along the northwest rift zone.

Six vents erupted lava between the late 1700s and 1801, two of which generated lava flows that poured into the sea along the west coast of the island. The Keāhole-Kona Airport, located only 11 km (7 mi) north of Kailua-Kona, is built atop the smaller Huehue flow (1801) just north of Keāhole Point.

Although Hualālai is not nearly as active as nearby Mauna Loa or Kīlauea, geologic mapping of the volcano shows that 80 percent of Hualālai's surface is covered by lava flows no older than about 5,000 years. In the past few decades, when most of the resorts, homes, and commercial buildings were built on the flanks of Hualālai, earthquake activity beneath the volcano has been low. In 1929, however, an intense swarm of earthquakes lasting more than a month was most likely caused by magma rising to near the surface. For these reasons, Hualālai is considered a potentially dangerous volcano that is likely to erupt again sometime in the next 100 years.