Professor of Mineralogy Otto Leidenbrock discovers a parchment within an old book that is filled with ancient runes. With the help of his nephew Axel, they are able to decipher the note, which claims that there is a crater in Iceland that holds the entrance to a path that leads to the center of the earth. Professor Leidenbrock immediately begins planning a journey to Iceland, and despite his fears, Axel agrees to join him.

In Iceland they obtain the help of a hunter named Hans, and make their journey to the dead volcano. They descend into the volcano, and head deep into the earth. After several days of travelling, but not finding water, they are forced to backtrack and take a different route. Hans discovers water when they are nearly dead, but must chisel through rock to obtain it.

They continue down further, but at one point Axel becomes lost, accidentally taking a different path. After wandering for days, he hears his uncle's voice travelling along the stone, and is able to find his uncle. He falls at the end, and wakes to light and the sound of waves.

They have discovered a great underground ocean, with giant mushrooms, and electricity formed light. Hans builds a raft and they set sail for the other side. While on the raft, they see two great, ancient dinosaurs do battle on the ocean. Then they find a giant geyser on a loan island. A massive electrical storm forces them aground. Their compass says they were turned around in the storm, and they believe they are back where they started. However, before they can set sail again, they discover a cave with the name of the ancient traveler who left the original note.

The cave, however, is blocked by a great stone, and they decide to destroy it in order to proceed. When they do, however, it causes the raft (which they were on at the time) and the ocean to pour into the newly formed hole. For days they fall upon the raft. Afterwards they begin to rise, however, and as the temperature rises it becomes apparent that they are riding the tide of what will be the lava from a volcanic eruption.

They are brought to the surface, and find themselves in Italy. They return home, and share their amazing discoveries. While many do not believe them, enough do and they become quite famous. Hans returns home. Axel marries his cousin Grauben.