Gunns Plains Cave, Show cave in Gunns Plains, Tasmania, Australia.

Gunns Plains Cave is a limestone show cave near Gunns Plains in north-west Tasmania, about 20 km from Ulverstone. Its public section runs 275 metres and holds stalactites, stalagmites, helictites and flowstone. Visitors enter by a steep, narrow staircase of 54 concrete steps cut into the hillside; a further kilometre of wild cave is harder to reach.

Bill Woodhouse discovered the cave system in 1906 while tracking a possum that disappeared into a hole in the ground. This chance finding led to the initial exploration and later development of the site for visitors.

The cave lies near Gunns Plains, the district named after Ronald Campbell Gunn, a Tasmanian botanist who documented the island's plants. Visitors today notice the wildlife rather than the botany: glow worms hang silk threads from the ceiling, and cave crickets and spiders live in the dark. The endangered Tasmanian giant freshwater crayfish also inhabits the cave.

Guided tours run daily at scheduled times throughout the year, providing a structured look at the cave system. The pathways are lit and fairly straightforward to walk, though the staircase descent at the entrance requires some effort.

The cave is home to the endangered Tasmanian giant freshwater crayfish, which lives in its waters alongside platypus, freshwater fish and eels. Glow worms hang their silk threads from the ceiling, and cave crickets and spiders are also present.